Cant find idle

[MOSHO92]

When i drop it into neutral while driving (like coming to a stop sign) the revs fall normally down to about 1.5k then sometimes drops down to like 400 rpm and stutters (almost dies) then it bounces up to 1300 again and then back down to 600 and then up to ....you get the picture. It finally smoothes out. What sensor could be going out? TPS, maybee the IAB. any advice? BTW i just got the 75mm proflow MAF, could that be the culprit? Thanks.

 

[NiNeTy Fo SHO]

I got the same problem...drops to ~400 rpm's, shoots back up to ~1300...but it only does it when the engine temp is below the normal range...once warmed up, she runs beautifully.
If you figure it out MOSHO92, please let me know.

Thanks.

 

[Chrisssssssss]

I would try cleaning the IAB and also switch out your MAF for the stock one. Don't forget to reset your computer so that it can reconfigure itself for the new MAF and IAB. see www.shotimes.com for the procedure on resetting the computer.

 

[svtC_and_SHO_Owner]

my idle is a lil jumpy too when shes cold. i cleaned the IAB, that seemed to help but didnt cure it. maybe now its cuz i dont have cats

 

[twr]

MOSHO92:
When i drop it into neutral while driving (like coming to a stop sign) the revs fall normally down to about 1.5k then sometimes drops down to like 400 rpm and stutters (almost dies) then it bounces up to 1300 again and then back down to 600 and then up to ....you get the picture. It finally smoothes out. What sensor could be going out? TPS, maybee the IAB. any advice? BTW i just got the 75mm proflow MAF, could that be the culprit? Thanks.

Does or did the car do this prior to the 75mm MAF install?? Runs fine with the stock MAF..

 

[MOSHO92]

Actaully it never used to do it before the new MAF, i did reset my comp. a few times trying to let the EEC figure it out but that didnt work. It mainly seems to do it when it IS warmed up, and especially after "spirited" driving. I wonder if pro-m has any sort of warranty, anyone have their phone number?

 

[AutoSHO]

MOSHO92:
Actaully it never used to do it before the new MAF, i did reset my comp. a few times trying to let the EEC figure it out but that didnt work. It mainly seems to do it when it IS warmed up, and especially after "spirited" driving. I wonder if pro-m has any sort of warranty, anyone have their phone number?

Check their website. http://www.pro-flow.com

 

[KevinShilley]

I am new to this Forum.....However I am an avid mustang enthusiast and it sounds like these cars have the same Fuel management system as their mustang brothers of the same era....so I will offer advice to try and help based upon that knowledge (since you guys are being so helpful in my hunt for an SHO)

1.) remove and clean The IAB valve
2.) check the voltage on the TPS
3.) Remove and clean the EGR valve

Whenever diagnosing drivability issues always do an EEC quick check/pull codes and make sure that the engine is otherwise in a good state of tune with no vacuum leaks ETC.

Good luck.....again, remember that I am basing advice on my mustang knowledge while trying to learn as much as possible about these cars before buying one, and trying to help those that are helping me in the process wink

 

[KevinShilley]

Also....Is your new MAF meter calibrated to your injector size????

And while Im at it what is stock injector size on these cars?

 

[Groo]

I'm pretty sure stock injector size on the 3.0 is 23.8# while the 3.2 is 24.4#.

 

[projectSHO89]

Kevin,

Welcome to this forum!

Yes, same engine management system as on any EEC-IV equipped Ford.

The IAB is responsible for maintaining idle speed and should be the first suspect when idle problems are encountered.

The TPS adjustment trick works on the SHO motor also, but not to any significant degree as it does on the 5 L V-8.

As for EGR, keep the following note handy:
ALL California have EGR
49 state MTX cars do NOT have EGR
ALL ATX (93-95) have EGR.

I dug up the following quote from my mailing list archives:
" I got this from John Hrinsin. It still is puzzling why Ford used two very
similar injectors, I think the MTX ones would feed the 3.2 L just fine.

MTX-23.65 lbs/hr static @2.7 BAR or 39.2 psi, Pintel type

ATX-24.05 lbs/hr static @2.8 BAR or 39.2 psi, disc type"

Steve

 

[NiNeTy Fo SHO]

I feel stupid for asking this, but...

What does IAB stand for and where is it located?

I feel like I know what it is...just cant remember headbang

 

[svtC_and_SHO_Owner]

IAB = idle air bypass. it basicly controls the idle. its right past the TB, the clyinder looking thing.