Throttle body cleaning went wrong (till now)

Owning my GRiSO 2009 it never had a great running engine.
It felt like misfiring between 2 and 3000 rpm. Idle was perfect.

Replaced all parts involved as leads, Phase sensor, spark plugs etc etc.
Last thing on my mind was throttle body cleaning.

Removed parts and yesss it looked necessary.[You must be registered and logged in to see this image.]

So started cleaning with carburettor cleaner and a toothbrush ( an old one)


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After starting the engine it runs worse than ever.

Do i have to anything with Guzzi diag?  it misfire terrible. Idle run at 2500 rpm.
What th hell did i do wrong??

Removed again for inspection but couldn't find anything (at sight) wrong.

Air leak? Were the boots seated and clamped correctly? Gaskets on the inlet manifolds damaged?

You didn't put carb cleaner in the idle stepper by any chance?

You mean false air? Soundslike i need to buy a cigar for a smoke / leak check. But yea it is possible. Thanks. I used new gaskets as seen in picture.

It looks like someone has messed with the LH throttle stop screw at some point. That could be bad.

You took the manifolds off. Why? And did you replace the manifold gaskets. There could be a leak there.

Are all the hoses connected to the airbox, stepper, blow by and the two drains? Are the drains complete and plugged?

Have you performed a TB balance? Did you clear the trims or disconnect the battery during this operation?

Going to check everything a second time.
Taking the manifold of made it easier. No need to remove the airbox.(no experience taking the throttlebody´s off)

Battery was disconnected.


To do:
Check hoses.
Do Throttle body balance.
Do TPS reset.
Self learning.
Make a video for learning purpose.

Measured distance the distance between throttle body stop's both wher closed. (measured with device to measure valves (voelermaatjes in Dutch)


Used new manifold gaskets so should be ok.
All hoses connected. Before cleaning the bike was stuttering from 2 to 3K rpm.
Can imagine that beyond 3K (higher rev's) it's hard to feel but could be there.

Yes the left hand throttle stop is questionable looking at he yellow paint.
Does TLM has a new set?  

I know this is a tough job and maybe not possible. Buying a second hand replacement will probably give same issue's. But why does it run after cleaning that bad?

Thanks all for reacting.

As can see the lh throttle stop seems to be messed with.
Rh throttle stop not.

This set up was ok with dirty throttle body's, but is not with cleaned. (or it is otherwise)
Cant get the idle to where de ECU want's it to be.

Now in a state of doing what Pete told us not to do.


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Quote :

Now in a state of doing what Pete told us not to do.

Stop. Don't.


You say it was idling well before you cleaned them? What RPM did it idle at?


Also, you didn't answer my question about carb cleaner in the idle stepper.

Beetle
I did no spray carburetter cleaner in the idle stepper.
Before cleaning idled at 1250.

Idea to block the stepper? I mean to block the left and richt throttle and see what happens?

Removed and installed everything for the third now with the most precision.

Same issue occured. What is it that makes it idle that high if it is not false air and everything closed?

Stepper stuck open would cause a high idle. Maybe not at 2500..that is more likely an air leak.

Just trying to cover all bases. It may be worth blocking the stepper inlet to see if there is any difference.

To me this, unfortunately, sounds pretty terminal.

If the throttle stop has been moved, especially if it is not known how much, and the TPS has been recalibrated then the baseline for the map has been lost. Now it may be that there is also wear in the TB spindle bushes and the throttle plates will of scalloped out the side of the choke of the throttlebody itself. Now previously this may of been partially occluded by the build up of mank in the TB’s and also the ECU will of been trying to, and to some degree, been successful in trimming around the changed air flow.

The problem now is that having disconnected the battery the trims have been lost and the TB’s now being clean the AFR at idle is going to be all over the place like a mad woman’s shit. Throw in the fact that the ECU is now working off an improper baseline and it’s going to make it very hard, if not impossible, to regain any normality.

In situations like these I never used to have much success in recovering function. Michael is a positive miracle worker in this regard and while he will be the first to tell you he’ll not be able to get it *Right* he often, I might even say ‘Usually’ manages to get some semblance of a working idle. There again he used to work at one of the best carburettor and fuel injection shops in eastern Oz so it’s not altogether surprising. That doesn’t really help you though.

This is, unfortunately, one of those cases where the only real fix is likely to be new TB’s. As a point of interest how much side to side play is there in the throttlebody spindles in their bushes? If you grab the bell crank arrangement on the left and, separately, the arm the linkage rod goes to on the right and you hold the throttle plates slightly open, how much side to side movement can you detect?

Pete,
No play felt. I sprayed carb cleaner while on it's side in it. Minimal leakage on both side. So it seems like all is closed.
But cleaning a carb will maker the engine does 2500 at idle seems strange to me.
In the afternoon perhaps time to close the stepper by hand. Last thing are the rubber o rings of the two new (deliverd by TLM) injectors. After thes actions i no there is no air leakage.

Will a second hand set throttle body's with all yellow paint in place be an alternative on a new set ?

To be continued

Deepdive, in Feb 2022, you said when you purchased the bike it had an idling issue? What did you do to fix that?

Last year, you installed one of my maps. You would have had to reset the TPS after installing the map (it's in the procedure).

In this thread's first post, you said idle was perfect. If so, then resetting the TPS wouldn't have affected it, given it has been remapped. Unless I am missing something? Did you actually reset it at that time, or was the bad idle fixed in 2022 by moving the throttle stop?


Curiouser and curiouser....

[quote="beetle"]
Deepdive, in Feb 2022,  you said when you purchased the bike it had an idling issue? What did you do to fix that?

Last year, you installed one of my maps. You would have had to reset the TPS after installing the map (it's in the procedure).

In this thread's first post, you said idle was perfect. If so, then resetting the TPS wouldn't have affected it, given it has been remapped. Unless I am missing something? Did you actually reset it at that time, or was the bad idle fixed in 2022 by moving the throttle stop?


Curiouser and curiouser....




When purchased there was indeed an idling issue.
The bike did not run for a long time before i bought it. But after let say 1000km the complaint was gone.

The complaint with not the best running at 2 to 3k stayed with whatever map i got. A bit more fuel for the bad range and trying diff CO (now on 6)
Yes followed procedure with the Guzzi Diag tool.
Replaced phase sensor leads bougies etc etc.

Finally can bring the GRiSO to TLM but maybe cheaper to buy a new throttle set. Simple install.

Just an idea about syncing TB's. If way out of sync and you screw in the balance screw to get the equal. You get to a point where you raise the idle mechanically. Even though they are balanced on the big end the idle will not come back down. I have had this issue when tuning the TB's.
There are only 2 alternatives, turn the idle stop and do not reset TPS(so you know where it's at) or go back to out of sync so idle comes down.
Could it be clogged bypass air screws? These are the only things i could come up with if all you did was clean TB's.

Edit: I am not saying to turn the idle stop screw, it should not be messed with.