B6 Stutter

[kzbill]

"xpnsyd", CEL, CAI of the P@P, cable TB, ???
I'm Lost

[25Horseplay]

Xpnsyd was Dj the former owner of ff.com, CEL is check engine light, CAI is cold air intake, I am not sure of p@p and cabl throttle body

[funky technician]

LOL cable throttle body is what our cars have, newer cars have electronic throttle bodies that use a servo, and P@P is port and polish

[25Horseplay]

Ahhh, port and polish.........................missed that one!

[funky technician]

hay kzbill, did you ever try to just grab your main wiring bundle in the engine bay and give it a good rattle when the engine is running to make sure you don't have a broken wire or something?

[kzbill]

yeah, I tried another Vaf also but it was used, not proven good, stripped the harness back and made sure the wiring wasn't scarfed or broken. tried another computer replaced the Ignition control module, TPS which was worn but functional. Rewired new fuses in using an aspire fuse block. got a new wire connector for the vaf, tried the shaking thing twenty times. I am being led to believe I may have had two worn out VAFs but am going to do some testing. Auto zone has Cardone VAFs for $82 exchange. unfortunately the correct way to check the VAF is with an oscilloscope.

[packrat427]

Nate look at this Vid and tell me if this is doing the same thing as your car ??

http://s48.photobucket.com/albums/f240/packrat427/?action=view&current=runproblem.flv

[kzbill]

That sure sounds related to the problem I have especially when it drops from 1500 rpm. that is the same dead sound I get when mine goes off. it's like it is starving but you can actually give it gas and it will just sit at 1500 and bog

[packrat427]

I cleaned my TPS contacts and sprayed it out with electrical contact cleaner , then I adjusted it to spec ,

It must have a little wear .

Here is my thread I had started over a year ago ..

http://www.fordfestiva.com/forum/viewtopic.php?t=7550&highlight=tps

I tried everything and the TPS adj is what stopped this .

If you look in that thread I posted how to adj. it .

If you have a repair manual it shows how to in there also .

[kzbill]

I posted this Sat, I went by the Haynes manual, and I will try it again.

Today I replaced the ICU, ignition control module, virtually no diff, maybe a slightly smoother Idle.
I did however try to set the TPS throttle position sensor using a dial indicator on the throttle stop instead of the feeler gages.
Interesting to see how really difficult it is that way. you can easily set the TPS to the .020 dimension, (see Haynes manual) continuity, no continuity and all that. but trying to set the .027 dimension is a real problem. I had to go up to about .060 then back to .027 to get it right. after all that I started to get the power loss, turn off the key, turn the key back on and start, thingy again. I drove it yesterday all day with no problem then today happened twice after setting it with the dial indicator.
I went back to the feeler Gage method and it is real hard to set the .027 dim. but it seems alright.
Maybe the problem is as simple as being able to properly set the TPS.??

this is a new theory.
I wonder if there is wear somewhere that makes it difficult to adjust it? Also the wear may make it set wrong. It is a new TPS so I have to check that too.
The dial indicator readings bug me. I should think they would be more accurate than the feeler Gage.
Also the videos of the idle oscillating between 100 and 1500 seems right about at the .020/.027 reading would be for the TPS, I think I need a big magnifying glass, indicator and volt meter or continuity light. the light may be better. you would think the dash pot would keep the throttle at above the .027 reading till it leaks down, then it would slowly go thought the .027 switch to the .020 switch. There are just two small reed switches in the TPS. I will have to check the throttle body shaft to see if that is loose in the throttle body too.

[skeeters_keeper]

Well mine idles really well now, however when i installed the new (new-used) TPS i just eyeballed it.

I also seem to be getting better gass mileage, but my fuel gauge is all over the place... sometimes at .8 tank, sometimes at .6 tank, within the same 10mi drive lol. The only problem right now is the check engine light, perhaps my TPS isn't adjusted right and that is causing it, seems like it from your other thread. I'll check that this evening.


thanks for the more info guys! hope we all get these little things figured out...

[kzbill]

hi guys,
next is a VAF weather or not I need it. mine are 17 yr old (both of them) and I don't want a problem again for a while.
autozone $81.99 exchange. Cardone with a 1 yr warranty.
I have a new TPS installed and a new Ignition control module. I swapped the dist already ( I have the one with the optical sensor and disc position sensor) new one is $172 + shipping at rock auto. I am not that rich at the moment.
I have adjusted the TPS many times now according to the book to no avail, not that I am ruling that out.
I am going to check for throttle shaft play that might affect the settings. and am going to try the indicator method for setting it again.
I have funeral today so I am not sure I will get to it. but those are my next plans of attack.
Thanks guys for the help and info so far.

[kzbill]

OK I changed the TPS to one I had, a "Denso". It was tighter than the new one.

The new standard motor products TPS had a great deal of slop or clearance on the little arm that drives the cam that actuates the switches or contacts. Made setting the ).027 dim. almost impossible.

I used a good throttle body with less shaft movement 0.006" lateral movement front to back.
I used a dial indicator on the side of the shaft at the end to measure the play, or clearance beween shaft and its bore.
the one I took off measured 0.010" lateral movement.
That might be enough to throw off the TPS setting. I thoroughly cleaned the throttle body and removed the Idle air control and cleaned the passages.

I did not change the Vane Air Flow Meter, although I have the new one. I didn't want to muddy up the diagnostic waters yet.
If this works.

I will have to test drive it to really find out if it works or not.

[kzbill]

No change, runs a little better becuse of the throttle body cleaning, but still did the stutter thing to me on a short ride.
Key on Key off and away it goes. usually happens after deaccelerating

[kzbill]

OMG!!!!!!!!! COULD IT BE THIS SIMPLE..................

I pulled the VAF and found the Ground bundle behind the air filter housing. I ass-ume that is the bundle that contains the ground for the VAF plus other critical components.

IT WAS LOOSE!!!!!!!!

could this be it?

If it is this could be the root cause, after all else is said and done.

Time to install the new VAF and do some testing.

If it is the ground that would be embarrassingly simple, but may be the problem that others are having.

If so I will take the embarrassement and hope it fixes it for all.

Bill L.