Article [13] ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Sounds like a good explanation to me Dave. I only manage enough miles to replace the tires once per year...
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Thought I'd post a follow up here regarding my suspicion of a failed open TurboTom thermostat. I pulled the thermostat this morning and it is not stuck open, and works as it should. See this thread (post #16) for a more detailed writeup.
:)
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Can anyone tell me where the screws to make the starter valve adjustment are?
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Can anyone tell me where the screws to make the starter valve adjustment are?

Are you really performing the Starter Valve Synchronization? I don't have a picture but if you look at page 5-79 in the manual (2003 edition) the second illustration from the top shows the location of the screws. You actually turn them with a wrench or socket. They don't look like a regular screw.
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

DD-
Editing my image from post #10, I've added red numbers directly over (hiding) the adjustment points for each cylinder's starter valve. So, you can go back to the image in post 10 and see what the red numbers are covering.
Starter Valve Adjustment points.jpg
Note: #1 is not adjustable but I've marked it for reference.

Is that what you needed?

:)
 
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Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Thanks Guys! I thought I had the right screws considering #1 is non adjustable but wanted to make sure. I did this on a V45 Magna I owned, of course it was carbureted.

As it turns out, I just put the gages on and there is no need for adjustment. All is well. Kind of happy I don't have to make any adjustment. However, while I had it running it blinked the FI light in a two-flash code. I hooked the sensor back up on the air box cover before starting it thinking it would not throw that code. Will it reset itself or do I need to do it? How?

I only did this procedure since I had torn down anyway to install the Audiovox.

Wish me luck!
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Thanks Guys! I thought I had the right screws considering #1 is non adjustable but wanted to make sure. I did this on a V45 Magna I owned, of course it was carbureted.

As it turns out, I just put the gages on and there is no need for adjustment. All is well. Kind of happy I don't have to make any adjustment. However, while I had it running it blinked the FI light in a two-flash code. I hooked the sensor back up on the air box cover before starting it thinking it would not throw that code. Will it reset itself or do I need to do it? How?

I only did this procedure since I had torn down anyway to install the Audiovox.

Wish me luck!

Yore welcome. :)

Check this thread out for resetting the ECM:
https://www.st-owners.com/forums/showthread.php?t=42235&highlight=reset+ECM
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Rerouted Throttle Body Synch Vacuum Lines. I rerouted the lines as shown below for easier line removal from the 5-way vacuum connector. Not only did this make the synch easier, but I think it helps reduce the risk of damaging something like the injector wiring/connections, MAP sensor, or starter valve linkage while trying to break/make the vacuum connections in their former location. In the picture below, the yellow, red, green, and white zip strips on each vacuum line indicate which cylinder the line attaches to; white=#1 cylinder, green=#2, red=#3, and yellow=#4.

That's interesting. Did you have to add more line or was the stock tubing long enough?
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Rob, the stock hoses are definitely too short for this mod.

I bought 1 meter of Honda's 3.5mm hose (95005-35001-20M "BULK HOSE"), item 26 on the fiche, and found that was not enough for what I wanted to do. So I went to a local Auto Zone and bought additional 1/8" vacuum hose. The 1/8" hose is slightly smaller and seats just fine onto the fittings.

In the picture above, the grayish colored hose between the MAP sensor and the 5-way connector is the Honda hose and the 4 black shiney hoses between each throttle body and the 5-way connector are from Auto Zone. :)
 
Re: First Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

This an old thread, but after reading I had an idea. Baker Boy had a great idea to extend the vacuum hoses for the sync hookup, but why not take them further? On a Vstrom, the sync ports are very difficult to reach, so its a common mod to install hoses that go all the way to the outside of the bike. If we took Baker Boy's idea further, the hoses could be extended to reach to either the valve covers or some other accessible place. With that you could check the sync at regular intervals without disassembling the upper fuel tank, air cleaner, or even the body plastic.

Anyone ever tried it? Looks like hose and vacuum T-s are the only needed components.
 
Re: ST1300-1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Don, thanks for the credit, but it wasn't my idea to move the 5-way vacuum connector.

I thought about doing what you suggest, namely to move the vacuum connector to a more accessible place. I did that on my VStrom and it makes sync checks a breeze. But on the ST1300, if you find the throttle body vacuums not even, youi'll still have to pull all that hardware to access the adjustment screws. Because of that I didn't route the lines to an even more accessible place.
:shrug1:
 
Re: ST1300-1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

Fast forward to March, 2011....

Yeah, this thread has morphed into more than just a report on it's 1st service--it's more like "my bike's service history" LOL.

My '04 dribbled quite a bit of coolant on the ground for a few minutes while in Hutchinson KS on March 28. The temperature at the time was about 27?F. (Thanks Follow for pointing out the leak!) The coolant leak surprised me as I normally see a few drips on cold mornings like that from the ever-leaky hose/connections under the throttle body. After the bike ran for a few minutes and the engine speed dropped to normal idle, the fast dripping tapered off and stopped. For the rest of that day it didn't seem to drip much, but it dribbled again the next morning (cold again). Each morning it dribbled enough coolant to cause a 6"-8" puddle under the bike--perhaps about a half cup ended up on the ground each morning because the overflow bottle was only about a cup low once I got home.

I was thinking the water pump seal was failing, or perhaps a hose to the wax starter valve was damaged enough to leak when the coolant flow was in bypass mode (thermostat closed).

The bike was also due for other servicing although I'd planned to delay the servicing after getting back from Moonshine. But that new behavior of spewing coolant on cold starts required attention so I pulled the bike apart when I got home and had to give up riding to Moonshine this year.

I did the following servicing from April 2, 2011 to April 7, 2011, the bike having 34,078 miles on the odometer at the time.

:radleak:Coolant Leak Investigation
As documented earlier in this thread, I had gone after coolant leaks a couple times in the past. Each time I was finding the hose connections slowly leaking as if the hose clamps were loose, so I'd tighten the clamps a bit more. But that proved only a temporary fix until the next winter had come and gone.

I pulled all the tupperware and removed the tank and air filter housing. But before I dismantled the coolant system, I borrowed NoBull's Ridgid SeeSnake, worked it in behind the thermostat, and started the bike. Within seconds a pretty fast drip was visible at the right cylinder bank 'water joint', where the hose connects to return coolant to the thermostat housing. I spotted no other leaks at that time, and I was relieved that the problem wasn't bigger. No coolant is draining from the water pump seal hole.
BB00194 coolant leaking before teardown.jpg

I had read for a couple years in other threads here where the coolant leaking problem was solved by replacing the stock hose clamps with constant tension clamps**, so I'd prepared to do the same and had the constant tension clamps on hand. I chose to do the clamp replacements from the front with the radiator and thermostat housing removed, rather than removing the throttle bodies that others have done. Doing the work from the front worked pretty well--it seemed easier than removing the throttle body assembly to me.
attachment.php


**Constant tension hose clamps: https://www.st-owners.com/forums/threads/st1300-solving-the-coolant-leak-problem-for-good.165403/
Clamp sizes https://www.st-owners.com/forums/threads/coolant-hose-clamp-sizes.156687/#post-1993326

It turns out that both the left and right cylinder bank coolant return hoses were leaking.
B4228 ST1300 Maintenance coolant thermostat hoses clamps.JPG
B4239 ST1300 Maintenance coolant thermostat hoses clamps.JPG
B4249 ST1300 Maintenance coolant thermostat hoses clamps.JPG

Look what was in the left cylinder bank coolant return hose! :eek: That would easily jam a thermostat, hopefully not closed!
B4241 ST1300 Maintenance metal shaving found in coolant hose.JPG
B4247 ST1300 Maintenance metal shaving found in coolant hose.JPG

One point about these constant tension clamps: these things are huge. If you do the same job, you'll want to think through how you'll orient each one and ensure you can both reach them to tighten them and also not get in the way of other parts that you'll reinstall, and also so that you can access the right cylinder bank cam chain tensioner release. I forgot about that last little point until I was doing valve shim changes the next day.
:doh1:

While the clamps are labeled 'constant tension', they're not constant given their design. They're much closer to constant tension than the stock clamps, so that's definitely a plus. But what I think is just as (or more?) likely beneficial is that they cover about twice the area of hose than the stock clamps. As such there is more uniform pressure over a larger area and the hoses aren't able to squeeze out from under the clamp (my opinion). Regardless of the reasons, I'm hoping that the leak problem is fixed for good. Here are a couple pics of the new clamps in place, utilizing the original hoses (I didn't have new hoses on hand or I would have replaced them).
B4257 ST1300 Maintenance coolant thermostat hoses clamps.JPG
B4260 ST1300 Maintenance coolant thermostat hoses clamps.JPG

While some folks replaced the original hose clamp on the front thermostat housing (upper right in the picture below) with a constant tension clamp of the same size as used in the above pictures, this hose is larger and I couldn't get satisfied with the fit of the constant tension hose clamp on it. A larger diameter constant tension hose clamp is warranted IMO. And that connection has never leaked so I took my chances and put the OEM hose clamp back in place. I'd like to have the larger size hose clamp, or perhaps a simpler spring hose clamp of proper diameter on hand for next service.
B4262 ST1300 Maintenance coolant thermostat hoses clamps.JPG

I finished putting the cooling system back together, ran the SeeSnake back in, and started it up. I was pretty tickled to find no leaks (and 1700 miles later it still isn't leaking).
:thumb:


:oilleak:Valve Checks
The two valve clearances that were at limits at last check (17k mi) were out of spec this time (34k mi). And I found a couple other clearances at spec limits so I decided to change them also. So I had to pull all 4 cams. Yuk. While putting in the constant tension hose clamps a day prior, I saw that cam chain tension release for the right cylinder bank next to the coolant hoses and thought 'that will be a challenge to access tomorrow during the valve checks' ... yep, it was. So I had to reorient one clamp from above (the one on the coolant return from the right head into the thermostat housing) to minimize interference.
B4295 ST1300 Maintenance right cams valve shims.JPG

I used a 'grabber' to remove and reinstall the cam chain tensioner cover bolt, it worked great. Here's a pic of me putting the bolt/washer back in place:
B4300 ST1300 Maintenance right cams valve shims.JPG

It took most of one day to do the valve clearances by myself, completing one side before opening the other. Below is how left bank and then right bank were oriented before disassembly, and how I kept the parts organized as I pulled everything. Since I had to remove the cams, I measured all shims and wrote the numbers down on the shop paper towels using a sharpie--numbers in magenta were the original shim thicknesses and numbers in teal were the replacement shim thicknesses. The pictures served as my documentation until later when I could get to a computer to save the information.

Left cylinder bank:
B4265 ST1300 Maintenance left cams valve shims.JPG
B4271 ST1300 Maintenance left cams valve shims.JPG
B4278 ST1300 Maintenance left cams valve shims.JPG

Right cylinder bank:
B4287 ST1300 Maintenance right cams valve shims.JPG
B4292 ST1300 Maintenance right cams valve shims.JPG
B4289 ST1300 Maintenance right cams valve shims.JPG

When I put each cylinder bank back together and rechecked clearances, all were nicely in spec. :thumb:

:radleak:Spark Plugs
As they've only got 17k miles on them, I pulled them and checked for atypical signs. All were matching, were good color with good electrode, ceramic, and tip condition. So I put them back in. Here's a sample:
B4279 ST1300 Maintenance spark plugs.JPG

:radleak:Lubed The Shifter Linkage
There are two small ball joints on each end of a tie rod, each ball joint covered with a rubber 'dust cover'. Of the two, the only one that I could easily get to is the low-right one, just forward of the center stand. That specific ball joint would be the one that has the highest chance of getting damage from road debris. I found the boot in good condition, but the grease inside was pretty gritty and runny. I cleaned it up, putting some fresh grease in place and slid the boot back over. The other ball joint is up high, well protected from any debris, so I left it alone.
B4408 ST1300 Maintenance shifter linkage tie rod ball joint boot.JPG

:radleak:Brake Pads
I'm still using the factory-installed brake pads. The measurements of the remaining pads thicknesses for the front 4 pads, left to right were: 3.5, 3.1, 3.5 & 2.0 mm. The new front pads I have on the shelf have 4.0 mm of material on them.

The rear 2 pads, left to right, measured 2.7 & 3.2 mm--the new rear pads on the shelf have 5.5 mm on them. I thought they'd be needing replacement soon, but to my surprise there's at least 40% remaining on the most worn front and rear pad.

:radleak:Hydraulic Clutch Fluid
The hydraulic fluid darkens quicker than the brake fluid and it's an easy change out, so that was done again. I decided the brake fluid can wait for another day this year, or a brake pad change, whichever comes first. I don't use a mighty-vac, but the old slow pumping method while manning the bleeder with a wrench.

:radleak:Electric Windshield
I opened up the windshield cowling to clean and lubricate the windshield slides. Last time after cleaning a lot of dark sticky grit off the slides, I used DuPont Teflon spray. This time I found the slides were surprisingly clean and easy gliding. So I gave another dose of Teflon spray to the slides after a slight cleanup. While in there, I opened up the motor/gear mechanism and found it to appear in good condition, so I sprayed in a little low viscosity lithium grease as I ran it up and down a number of times.

The upper fairing deflector set has adhesive on it that joins both the windscreen cowl and the panel that surrounds the instrument cluster. Every time I access the windshield slides, that upper fairing deflector adhesive has to be replaced. And the topmost removable rivet, which is supplied with the fairing extenders to join the fairing extenders, the upper cowl, and the windscreen cowl has never fit well. I replaced it with a standard Honda low profile 'splash clip' (see red arrow in picture). While I like the looks of that fairing extender, it sure could have been designed better IMO,
B4320 ST1300 Maintenance upper fairing deflector reinstalled flush mount rivet.JPG

:radleak:Warm Weather Surging
I still haven't figured out the source of this issue, but when the bike becomes heat soaked, such as after sitting for ~10 minutes, especially at high altitudes, it surges very abruptly at low RPMs and hammers the drivetrain. The problem appeared with no warning several summers ago, months after any service. In trying to diagnose the problem, I've replaced the MAP sensor, replaced the fuel pressure regulator, checked all vacuum lines and electrical connections, and replaced the fuel filter. But it still has this high temperature surging.

So continuing to work on this, I changed out the fuel pump to newer used one I bought from a parted out bike. A couple years ago I put the stock FPR back in place to ensure it wasn't a faulty FPR, and since that had no effect on the surging, I put the TurboTom FPR back into the bike to dampen some of the ST's notorious throttle burst. I also disconnected, wiped, and used dielectric grease on all the connections (including coil connections) that I could access on the bike. I also pulled all the vacuum lines and the 5-way tee... all were super-clean inside with no debris.

I rode through KS & OK a couple days ago where the temps were upper 80's, and did not have any hints of surging. But when I got to higher altitudes on my return trip yesterday, even with cool air temperature, the bike started showing some signs of the problem following riding breaks. Bummer, its not over yet.

At this point, about all that is left is the IAT (I have a spare) and the coils.
:shrug2:

:radleak:Starter Valve / Throttle Body Synch
With the valve shim changes, the idling vacuum changes a bit. So I hooked up my Morgan Carbtune and found slight adjustments were necessary. The vacuum as found is shown below, cylinders 1 to 4 left to right, respectively. When that balance is achieved, the idle RPMs picked up nicely. Ah, it idles smoother now!
:D
B4311 ST1300 Maintenance starter valve synch throttle body vacuum as found.JPG

:radleak:Upper-Lower Fuel Tank Hose
A prior one I bought was about an inch too short. I bought another new one, and it is better but was still ~1/4" shorter than the original! the shorter the hose, the higher the likelihood of it being damaged on tank lifting. Why is Honda shortening it?!
B4317 ST1300 Maintenance fuel tank joint hoses.JPG

:radleak:Other Stuff Done
--lubed the wear points on the side & center stands
--checked rear drive oil
--major cleanup on reassembly as I hadn't cleaned it following the snowy return ride from Hutchinson

I put about 30 hours into the above work. I tend to take my time, but hey the price is right and I know the work was done right! :D

:hat3:
Ready to ride...I left the next morning for a 2-day 1675mile ride.
B4327 ST1300 Maintenance put back together and cleaned up.JPG
 
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Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

Nice write-ups John. Hope you had a good trip.

You ought to try fitting a Fuel Cut Eliminator to address the 'stutter' from a closed throttle.
 
Re: ST1300-1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Other

From April 2011...
Warm Weather Surging
I still haven't figured out the source of this issue, but when the bike becomes heat soaked, such as after sitting for ~10 minutes, especially at high altitudes, it surges very abruptly at low RPMs and hammers the drivetrain. The problem appeared with no warning several summers ago, months after any service. In trying to diagnose the problem, I've replaced the MAP sensor, replaced the fuel pressure regulator, checked all vacuum lines and electrical connections, and replaced the fuel filter. But it still has this high temperature surging.

So continuing to work on this, I changed out the fuel pump to newer used one I bought from a parted out bike. A couple years ago I put the stock FPR back in place to ensure it wasn't a faulty FPR, and since that had no effect on the surging, I put the TurboTom FPR back into the bike to dampen some of the ST's notorious throttle burst. I also disconnected, wiped, and used dielectric grease on all the connections (including coil connections) that I could access on the bike. I also pulled all the vacuum lines and the 5-way tee... all were super-clean inside with no debris.

I rode through KS & OK a couple days ago where the temps were upper 80's, and did not have any hints of surging. But when I got to higher altitudes on my return trip yesterday, even with cool air temperature, the bike started showing some signs of the problem following riding breaks. Bummer, its not over yet.

At this point, about all that is left is the IAT (I have a spare) and the coils.


For those not aware, the surging I experience on this bike is often associated with high altitude and elevated temperatures and low fuel level. However, it also happens with a full fuel tank, prominently at low RPM, and while not at high altitude. By 'surging', I am not referring to the 'instant on power' that this Honda FI system exhibits, but rather a harsh repetitive surging-dieing-surging that happens while holding the throttle constant. It will clear up within minutes of moving briskly and cooling off the internals of the bike. The surging is harsh on the drivetrain, and the only way to deal with has been to feather the clutch and hold the RPMs up and slurk away as the engine sputter and drivetrain hammer is downright embarrasing (Harley riders look and stare). :eek:

Over the recent couple years, the surging had become so bad that it would happen even at 'lower' altitudes and without the bike getting heat soaked. So this spring I put in a donor (used) fuel pump assembly I got on eBay at a good price.

Fast forward 4 months and 7,000 miles...

That used fuel pump has reduced the warm weather surging, but the behavior still shows up at times. Wifey and I were on the bike in Leadville a few weeks ago and I had to negotiate a bunch of deep gutters and frequent stop signs on side streets as they had the main street closed ... of course the bike starts hammering and surging and I almost dumped the bike with her on it.
:mad:

That was the last straw. So, I bit the bullet and ordered a new fuel pump and associated lower tank fuel gasket from RonAyers.com:
16730-MCS-G00 PUMP SUB-ASSY., FUEL 1 $208.09
17574-MN5-000 GASKET, BASE 1 $6.02
(plus $20 shipping)

Earlier this week, I took the 20 minutes to get the new pump installed into my OEM fuel pump assembly (which has a new fuel filter in it), and then another hour to install the new pump assembly into the bike. The used/donor fuel pump assembly is now back on the shelf.

So yesterday I filled up the bike and headed to high country. Several times I let the bike sit and heat soak, I ran the fuel low, ran it at low rpm while heatsoaked, and I ran up Cottonwood Pass (nearly 12,000 ft altitude) and let it sit for a bit ... ... ... to my surprise, the surging appears gone ! ! !.

I was able yesterday to run the bike normal -- like it was new!

fingers crossed.jpg
I'm keeping my fingers crossed that the fuel pump is the whole problem. This summer I had ruled out fuel pump and was searching for other gremlins since the donor fuel pump was installed and the bike still produced surging. After all, what are the chances that a second fuel pump was bad?! Apparently, pretty high.
:doh1:
 
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Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

Hopefully that fixes it.
iirc that was Kempo sans issue. Fuel pump pressure tested ok, fuel flow did not.
That surging somehow took out the clutch and the clutch basket.
 
Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

I have put 3,000 miles on it since the new fuel pump was installed. The new fuel pump has helped in many of the situations where it would have surged/sputtered and hammered the drivetrain in the past. The surging is greatly reduced but is not entirely gone.

In Moab a few weeks ago at 95?F, I'm slowly making my way through town on Hwy 191 when I back off the throttle due to vehicles in front starting out from a stoplight--as soon as I cracked open the throttle, it spasm'd twice (sudden power on-off-on-off-on) and then it pulled normal before I had much of a chance to do anything. That one caught me off guard as I'd gotten lulled since the pump replacement.

This past weekend, I barely got the bike started trying to get to my RTE. I cycled that new fuel pump many times and cranked and cranked on it. It eventually started lightly firing on one then two cylinders (enough to keep running with the aid of the starter motor), then three and four fired and it ran normal. The difference this time was that I let it set for a couple weeks with a half-full fuel tank, which I had not done all summer.

Later in that same day, I was making my way through Dillon (9,000 ft elevation) through stoplights and it starts sputting and knocking at low RPM (like the timing is suddenly very wrong). I run the RPM up a couple thousand and it clears up.

Given these couple instances, it appears there still is something to address.

Overall, that behavior is pretty minor compared to what it used to do and I credit the improvement to the brand new fuel pump. I would buy another fuel pump or assembly in a heartbeat if it again digresses to the condition it suffered over the last few summers.

:thumb:
 
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Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

.... Fuel pump pressure tested ok, fuel flow did not.
....

The idea that pressure tests ok but flow is insufficient never has set right with me. :confused: (Not poking at you Carl, but rather just still stumped at the idea.)

Being an engineer, I know that a pump installed within it's normal system has not delivered normal flow if did not attain normal pressure, and vice versa. Hence that is why most fluid pump systems in plants have pressure gages attached--one doesn't need the complexity of a flow gage. The pump can't make a pressure if the flow has not been met, and vice versa. Pressure only rises to 'normal' levels if it has delivered sufficient flow for the application and it begins to press into a well packed fluid. Much like electrical power in circuits, V*I isn't attained if the power supply [fuel pump] can't attain either voltage [fuel pressure] or current [fuel flow].

:shrug1:
 
Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

That's how it's described but I don't know the test.
(2 gages and and orifice?)

Could be dead head pressure was ok but couldn't maintain svc pressure with flow?

I'll ask if I can mooch a tire change

Does a gear pump (I'm assuming it is one) follow a normal pump curve?
 
Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

Yes Tom, I have swapped back and forth between the OEM and the TurboTom. TT is currently installed and it does soften the transition when opening the throttle from a closed position.
 
Re: ST1300 - 1st Significant Service: Coolant, Thermostat, Starter Valve Synch, & Oth

What about 1 or both O2 Sensors switching too slowly. It would be enlightening if you could graph their output on a handheld VSO. I think the ST uses O2 signals
for a large portion of the fuel mapping and a slow responding one can cause the engine to fall on it's face under certain lean conditions.
 
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