[jrichker]

Originally Posted by willys1

Awsome I couldnt find it,but someone here on SN gave it to me so I knew it would show up!!,,My idle seemed fine today..I guess it needed a full cool down to compinsate for the cleaned IAB But it still stalls when I start it in the morning.....This thread is a great idea

Check & clean the IAB electrical contacts & the 10 pin connectors too. If that doesn't fix it, I would look into replacing the IAB. The cold stalling is a clue to a non-functional IAB.

[blown93feature]

Hey guys, I read through the posts on this subject and I used the some of the technics to help find my gremlins.
Thanks, Joey.

[2dr_sedan]

$7 fuel filter, now my car runs smooth as silk... All this time it's been the freakin fuel filter...

[ImportEater98]

My 89 LX idles right at 900-1000 steady on a cold start.....closed loop.
As soon as it hits operating temperature it starts bouncing 700-900 rpm.
From there the idle sort of "bucks". Soon it becomes such a "buck" that it stalls the car. I have an E-303 cam and i know someone mentioned that they are notorious for that problem.
Now that i know the problem is only in "Open Loop" operation, is there anything i can eliminate right off the bat as i try to trouble shoot?
It can't be a vaccum leak or it would happen in both open and closed loop, correct?

[HISSIN50]

Originally Posted by ImportEater98

My 89 LX idles right at 900-1000 steady on a cold start.....closed loop.
As soon as it hits operating temperature it starts bouncing 700-900 rpm.
From there the idle sort of "bucks". Soon it becomes such a "buck" that it stalls the car. I have an E-303 cam and i know someone mentioned that they are notorious for that problem.
Now that i know the problem is only in "Open Loop" operation, is there anything i can eliminate right off the bat as i try to trouble shoot?
It can't be a vaccum leak or it would happen in both open and closed loop, correct?

I might be loopie (well, we know that), but I think you have your loops backwards.
OL is when O2's are not used (Cold motor, WOT, etc).

CL is when the motor is warmed up a little and O2's are used.

I wanted to make this distinction - people who reply would probably want clarification. good luck.

[ImportEater98]

ugh...im so stupid. Typed that post with a few beers in me. You are right hissin......basically switch the closed loop to open loop and vice versa in that post. Sorry bout that

[super302]

Thanks,
A combination of things fixed it....all for a $3 can of throttle body cleaner

[Tuff02Ranger]

I've tried just about everything listed here, and I still have a surging idle. But mine goes from like 700 up to 1300 RPM's. I'm also running very rich. My car was fine before I added the supercharger, 255lph fuel pump, and 30 lb injectors. Also went to a 76mm MAF. If I unplug my MAF, it won't surge anymore. I've cleaned the IAC and throttle body and still no luck. My brother thinks that putting in a Kirban FPR will fix my problem. Does that sound right? Between regulating fuel pressure and adjusting my timing, should that fix the problem, even though unplugging the MAF stops the surge?

[willys1]

Originally Posted by jrichker

Check & clean the IAB electrical contacts & the 10 pin connectors too. If that doesn't fix it, I would look into replacing the IAB. The cold stalling is a clue to a non-functional IAB.

I went to Hackettstown Ford today and ordered a new IAB,it should be in next week.97 beans

[jrichker]

Originally Posted by Tuff02Ranger

I've tried just about everything listed here, and I still have a surging idle. But mine goes from like 700 up to 1300 RPM's. I'm also running very rich. My car was fine before I added the supercharger, 255lph fuel pump, and 30 lb injectors. Also went to a 76mm MAF. If I unplug my MAF, it won't surge anymore. I've cleaned the IAC and throttle body and still no luck. My brother thinks that putting in a Kirban FPR will fix my problem. Does that sound right? Between regulating fuel pressure and adjusting my timing, should that fix the problem, even though unplugging the MAF stops the surge?

Try cleaning the MAF element & then "clock" the MAF to see if changing its position helps any.

[willys1]

Originally Posted by jrichker

Try cleaning the MAF element & then "clock" the MAF to see if changing its position helps any.

Yeah,I would try turning the MAF,its worked for me.Turn it 180 degrees towards the motor.

[Don Fiveolio]

Alright,

I'm starting to have the same issue with my Stang and I think I have found the problem. I'ts most likely the IAB and I want to clean it out, but I don't know what to use.

What are you guys using?

[89MustangGX]

Originally Posted by don herberto

Alright,

I'm starting to have the same issue with my Stang and I think I have found the problem. I'ts most likely the IAB and I want to clean it out, but I don't know what to use.

What are you guys using?

Carb cleaner or similar. May need to use a screwdriver if it's REALLY bad...just be careful of the rubber seal part inside.

[Don Fiveolio]

Here's a question that is a little of topic, but deals with the same situation. I pulled the IAB last night and cleaned the ports on the side of the throttle body. I put everything back together and now the surging idle is worse.

While I was cleaning, I decided to pull the throttlebody and the gasket was horrible. I figured this might be a part of the problem so I headed right out to the parts store and bought a brand new gasket, but this is the thing:
Do I need gasket sealant for this application?? I could not tell because everything got soaked in coolant. The guy at the shop said I should get it and sold me a tube, but I thought I would get some feedback before I started.

Any hints??

[jrichker]

Originally Posted by don herberto

Here's a question that is a little of topic, but deals with the same situation. I pulled the IAB last night and cleaned the ports on the side of the throttle body. I put everything back together and now the surging idle is worse.

While I was cleaning, I decided to pull the throttlebody and the gasket was horrible. I figured this might be a part of the problem so I headed right out to the parts store and bought a brand new gasket, but this is the thing:
Do I need gasket sealant for this application?? I could not tell because everything got soaked in coolant. The guy at the shop said I should get it and sold me a tube, but I thought I would get some feedback before I started.

Any hints??

I would use some RTV sealant since you are mating a water jacket (TB water cooling) to a part that has engine vacuum.

[Black Sun 5.0]

Definitely check all grounds. I had a problematic DC Control unit for my electric fan. I replaced it and all the associated wiring, surge is very rarely a problem now where it had once been stalling all the time. I doubt the issue was with the controller, the grounds made more sense.

[5.02GO]

Thought i read that someone wanted a part number on a bypass plate.


Well, here is a link to mustangs unlimited. "Idle Adjustment Plate".
I think its a must for "E" cam users. Mine would NOT hold an idle until i installed this plate. I realize this may not have alot to do with the original subject thread but here is the link just incase someone needs this.

http://www.mustangsunlimited.com/ite...=&catkey=74-01

[Marshall]

Great thread - It has been suggested that a final checklist be written with all the possible checks. Please someone do this so us dummies can download it for future reference.

Thanks

[BERT306]

I just found that i had a X3Z computer in my 90LX, not the A9L. Had to get a calibration tube for my 76MM C&L
MAF to match the X3Z. Runs GREAT now!!!

[aete2]

thanks guys forthe list huge help

[HISSIN50]

Originally Posted by BERT306

I just found that i had a X3Z computer in my 90LX, not the A9L. Had to get a calibration tube for my 76MM C&L
MAF to match the X3Z. Runs GREAT now!!!

Is the X3Z puter not a cobra unit? If so, it seems to me that the puter calibrates for 24# injectors itself (in case an issue pops up for you Bert).

Good luck.

[mkkrs1]

If you replace the TPS or IAB. do they have to be set or is it a simple remove the old one and install new. are there any checks to perform to see if the TPS or IAB are still good before you purchase new ones not needing them.



mike 89-718

[HISSIN50]

Originally Posted by mkkrs1

If you replace the TPS or IAB. do they have to be set or is it a simple remove the old one and install new. are there any checks to perform to see if the TPS or IAB are still good before you purchase new ones not needing them.



mike 89-718

Jrichker has some wonderful write-ups he has posted on peoples' threads. I would search each term above using the search feature, or search JR's old posts. You should find what you want.

Good luck.

[crenth5]

My engine doesn't surge, but if you get it over ~2000 RPM's it comes down to 16-1700 and just sticks until you come to a stop. I cleaned the IAC and did't help. I tried turning the IAC upside down and it was worse. I cleaned the MAF tube and that didn't make a difference. Haven't cleaned the element in the MAF yet. I have the idle set at 7-800 and the TPS is somewhere around .95, not over 1. I DO have an E-cam, but it doesn't have a rough idle, it just sticks. I lloked for the 10 pin connectors and couldn't find them. Anyone else have this similar problem?

[kr mstg]

I would also recommend checking and replacing the pcv valve, grommet, and the wire mesh in the back of the lower intake. ( falls under vacuum leaks)