Hesitates during acceleration/WOT

[shooff1994atx]

Hey, I have a 91 SHO Plus. I am trying to narrow down the problem I have, I know the Tie rods need replaced, but when I am driving and try to accelerate normal and floor it the engine feels like it is missing and barely goes anywhere, very sluggish. bought the car for 300 bucks, so I cant expect too much. I bought a code reader, but I have no 9V batteries so I can run the codes right now. No CEL light but its worth a try to see if there are any stored. I bought a new TPS, Plugs, plug wires, I have cleaned the MAF, no oil in the plug wells. I am trying to eliminate everything, There are two ports that look like cavuum lines should go to that is apart of the throttle body at the bottom. one facing the engine on the front side and one facing down on the back side, are those supposed to be open? also there is a plug under the throttle body that isnt connected to anything, kinda big/light grey what does that go to? Im hoping it isnt crank cancer, or dead cylinder. but i figured Id ask you guys since this site is very knowledgable and ive been out of the SHO scene for awhile now messing with DMS's. a different kind of pain in the a$$ than SHO's. I will pull codes tomorrow, just seeing what you guys had to say. thanks

 

[FastAndFurious]

You don't need a code reader to get the codes.

http://www.shophoenixproject.com/eec/eec.htm

All you need is a piece of paper, a pencil, and a paperclip.
Yeah I would definitely get the codes first, and then go from there.

Those two ports are for coolant hoses. I guess someone did TB coolant bypassing.

I don't know what that connector is. I will probably go look at mine in a little bit.

 

[shonuffmine]

X 2 on the tb bypass.check all your grounds wires

 

[shooff1994atx]

codes checked out good...I got 11...and wish I would have read into the paperclip method.. Oh well. I bought that cheap 29 dollar one from AZ.

 

[shooff1994atx]

sorry that was koeo, koer is 17 and 19

 

[shooff1994atx]

and how the H**L do you remove this PCM? Im trying to swap it out with another I have..but I cannot remove it..I removed the bolt from the firewall, I removed that clip inside the glove box. Im trying to remove the connector under the hood, it isnt working out, and i have a pair of pliers pulling from the glovebox and still no budge..hooray for bloody knuckles!

 

[ShadetreeSHOguy]

What kinda wires did you put on it?

 

[shooff1994atx]

What kinda wires did you put on it?

motorcraft plug wires are installed

 

[shooff1994atx]

new set of codes today...

12 Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too low) - ISC

13 O) ISC did not respond properly (extends to touch throttle then retracts for KOEO) - ISC(R) Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)(M) ISC sticking, open ITS circuit or TP sticking

15 (O) No Keep Alive Memory power to PCM pin 1 or bad PCM (Memory Test Failure)(M) KAM (pin 1) was interrupted (was battery disconnected ?)

17 1.9L & 2.5L - Throttle stop set too low - IDLE

19 O) No Vehicle Power (pins 37 + 57) or bad PCM VPWR Diagnosis
(R) Erratic idle during test (reset throttle & retest) - Idle Set Procedures
Electronic ignition Cylinder ID sensor/circuit problem - Ignition Systems

would any of these cause my symptoms listed in the first thread?

also today I swapped my PCM for another one I had laying around (finally got it removed)..the car seems to run the same..havnt driven it yet, but I do notice the idle is alot quieter with this PCM than the other one I had installed.

 

[SHOspazz92]

If you were not 2 hours away (I'm near Siler City), I would drive down with my box of spare sensors and let you have a go at it. However, Since I'm lazy... you can drive up to my place if you wish and have at it.

-Sam

 

[shooff1994atx]

If you were not 2 hours away (I'm near Siler City), I would drive down with my box of spare sensors and let you have a go at it. However, Since I'm lazy... you can drive up to my place if you wish and have at it.

-Sam

ha...might have to take you up on that offer..but I dont trust the SHO driving that far, maybe when I get the Tie Rods replaced. there is a salvage yard here, on saturdays you can pull whatever you want and its 40 bucks..I might just start cutting all the sensors off one of their SHOs and maybe find the culprit. im definately getting an engine from there to rebuild.

 

[SHOspazz92]

ha...might have to take you up on that offer..but I dont trust the SHO driving that far, maybe when I get the Tie Rods replaced. there is a salvage yard here, on saturdays you can pull whatever you want and its 40 bucks..I might just start cutting all the sensors off one of their SHOs and maybe find the culprit. im definately getting an engine from there to rebuild.

Why would you rebuild it? I'd replace the rod bearings, Do a Full 60k and call it a day.

The engine in my track car (That has seen 8500 RPM quite often) has nearly 240,000 Miles on it, With only the main (Not necessary) and rod bearings having been replaced (On top of a 60k Service). It runs perfect.

-Sam

 

[shooff1994atx]

Why would you rebuild it? I'd replace the rod bearings, Do a Full 60k and call it a day.

The engine in my track car (That has seen 8500 RPM quite often) has nearly 240,000 Miles on it, With only the main (Not necessary) and rod bearings having been replaced (On top of a 60k Service). It runs perfect.

-Sam

sorry, I should have said 60K..thats what I meant by rebuild..i mean for $40 bucks I dont care what shape the engine is in..

 

[FastAndFurious]

sorry, I should have said 60K..thats what I meant by rebuild..i mean for $40 bucks I dont care what shape the engine is in..

Have you done cylinder balance test as well? I would do it just for the heck of it if I were you.

From the codes, it seems like either your pcm or wires to the pcm is messed up, and also, clean out IAB.

Just FYI, I had hesitation during acceleration and wot, and the problem was the wires, but I don't think it's your case.

 

[shooff1994atx]

Have you done cylinder balance test as well? I would do it just for the heck of it if I were you.

From the codes, it seems like either your pcm or wires to the pcm is messed up, and also, clean out IAB.

Just FYI, I had hesitation during acceleration and wot, and the problem was the wires, but I don't think it's your case.

I have not done the cylinder test. well I just drove the car to see how the other PCM did..the car drove alot better it seemed...didnt hesitate as much as it did. I also put a different MAF on it as well..the old mass air flow unit was an 85mm c&l with the stock maf sensor..would that have caused my problems?

 

[SHOspazz92]

I have not done the cylinder test. well I just drove the car to see how the other PCM did..the car drove alot better it seemed...didnt hesitate as much as it did. I also put a different MAF on it as well..the old mass air flow unit was an 85mm c&l with the stock maf sensor..would that have caused my problems?

YES!

An 85mm Unit with a stock Tune is a disaster.

Put a stock one in and it should run a lot better.

-Sam

 

[shooff1994atx]

YES!

An 85mm Unit with a stock Tune is a disaster.

Put a stock one in and it should run a lot better.

-Sam

thats what I thought after reading alot of posts, I thought the MAF looked different so I pulled it..and saw it was a C&L..like i said the car is running better now..thanks for the help everyone.

 

[Vnuk1]

Try driving with your MAF unplugged.....

 

[shooff1994atx]

driving with the maf unplugged was a no go..car wanted to die when I let off the gas.