98 slowbra help

[98cobrafaf]

i have a 98 cobra with 3.73 gears 6 speed and aluminum driveshaft.
186000 miles compression is still great.
when i get on my cobra and get up about to 4500rpm my car falls right on its face ,no pull and it likes to cut in and out and idles weird sometimes i have replaced the fuel filter ,fuel pump ,spark plugs and wires ,mass air flow sensor,
it keeps throwing the imrc code but they seem to be opening i have my friend rev the engine and i feel them opening. i have had them out and cleaned them.any ideas of what it could be. and it stil;l does everything

 

[mpe331lx]

Do you have a fuel pressure gauge? If you do, hook it up and tape it to your windshield. take the car for a spin and monitor fuel pressure. just because you replace the pump, does not mean that you dont have a fuel delivery issue. Could be the fuel pressure regulator.

 

[98cobrafaf]

yea ill try that

 

[98diablo]

i had the same problem once it ended up being the msd coils. i put the stock ones back on with no problems since

 

[98cobrafaf]

thought i had a fuel pressure gauge but didnt ill have to go out and get one from my buddy at the shop..
i went out and bought a fuel pressure regulator didnt change a thing .
my check engine light just went off this morning but sure it will be back on.
i have bought coils and put them on didnt chang a thing so i just took them back

 

[Toasty]

IMRC controllers are bad if you are continuing to get IMRC codes thrown AND you have cleaned/checked their operation.

 

[98cobrafaf]

yea i have cleaned and checked their operation i let my friend rev my engine and they open.
ohh and its really sluggish after about 70 and 80

 

[98cobrafaf]

still having problem anymore ideas

 

[98cobrafaf]

bump

 

[mustangcobra98]

when if falls on its face at 4500 whats it sound like? have you checked all your vacuum lines? i know they make our cars do crazy things sometimes. yours has quite afew more miles on it than mine. but I'd love to know what the fix is when you get it. I have a 98 also.

 

[ksigatmsu7f02]

IMRC controllers are bad if you are continuing to get IMRC codes thrown AND you have cleaned/checked their operation.

+1
Not much else going to throw an IMRC code....

 

[Shake&Bake]

+1
Not much else going to throw an IMRC code....

They might be opening, but all the way? This would explain the strange performance issues.

 

[98cobrafaf]

it has a different tone it screams at the lower rpms and gets more boggy the higher its like holy shit to about 4500 and then its like what the hell

 

[98cobrafaf]

i made my old imrc into deletes and put them on and lodt alot of tq but now it startes falling at 5

 

[298 snake]

just to let you kno u kno that the imrc and vaccum controlled and electronically controlled so either the its not pulling the vaccum or inside of the contron module you need to get down to the controll module get a volt meter do a voltage drop test on the brown wire and see wat voltage u pull should be 5mv

 

[Blu50Stang]

+1
Not much else going to throw an IMRC code....

Agreed. But if he can verify that both sides are opening normally then that is not the problem.

My wife's 97 kept throwing the same 2 codes (both pointing to an IMRC problem). I cleaned the IMRC plates, replaced the actuator with 2 working (used) units and 1 BNIB unit before learning the problem was a bad ECU. Each time, I could feel the IMRCs would work sproatically at best. Each time, the car had no power over 4-4500 rpm's. Had to have Ford look at the car.

 

[Termi 03]

yea he said he did the imrc delete and still no change