Weird Idle Problems

[lndshark]

HI all, have searched for a week to try to find the answer to this problem with my 93 MTX but to no avail.

Had work done on m car, rear brakes, new belts. Drove it one mile the next day, ran fine. Left it parked there for 2 days, went to start it up and the idle would fall to about 500 RPMs then kick back up to 1500 or so, just a continuous process. Must be the IAB, right. I drove it to my parents this weekend, I lack a garage. It stuttered and lurched a bit at first then smothed right out. By the time I got to my parents it was idle much better. The check engine light did come on, so a code was set. I cleaned the IAB and then cleared the momory as instructed to do on shotimes. Started it up and it still had the wokey idle. I drove it round the block three times and it idled like a champ after that. This morning, it did it again, wonkey idle, then after i had driven a mile or so, it idled perfectly. It did set a code again. I will pull that tonight and post.
I would appreciate any help as i need to sell this car. I just want to make sure its in tip top shape before i let it go.

Anyway would appreciate any responses. Thanks

 

[lndshark]

Just pullled the codes, they are 543, 117, 122, and 126

thanks

 

[todras]

Just pullled the codes, they are 543, 117, 122, and 126

thanks

Had same problem forever. Changed IAB, ECT, fuel pump MAF & TPS in that order. MAF & TPS finally fixed it. Try a new TPS. $20.

 

[sdpatt]

Too many sensors out of range on a single wiring harness (ECT, TPS, BAP?) to be coincidence. Also check the connectors on the DIS module.

 

[lndshark]

Does that mean I have a bad harness? What do I do about that./

Gadzooks. Im already upside down in this car, for what i bought it for and and the money i have put into it, and what ill be able to get out of it. Oh, well I guess thats what you get for loving these stupid cars.

 

[stevemainian]

You may want to look into O2 sensors.

On older Fords like the SHO, faulty o2 sensors will cause problems exactly like yours.

I had the same problem and i replaced the o2's, and the problem was fixed.

 

[mkostinec]

I just fought a strange idle problem. Ended up being the IAB and the MAF senors. But then again I changed so many sensors I really don't have a good idea. I just happen to change out the MAF and IAB last - the easiest to change out!! Also changed out the TPS - not sure if it was bad.

Buy the parts - MAF, IAB, TPS, and O2 sensors - you will need them sooner or latter - more likely sooner. Most O2 sensors should be changed somewhere between 30K and 50K - but they could last longer.

 

[lndshark]

Got the whole thing figured out. Took it to the mechanics next to my store, the idle problem, and there was a fule pressure problem that would pop up from time to time. Along with the code i got for engine temp sensor to high. All signs led to a relay box, not sure where, or anything else about it. They found a used one for sixty bucks. Car runs great now.