98 cobra falls on face...

[jj98cobra]

Well this all started about a month ago. I found out the parts dept at my local dealership ordered the wrong battery. My car sputters out and dies on my way to work. Picked up the correct battery. Fired right up drove it home and to work for a week or so and noticed a ”pulsating” idle. Just figured it was a vaccuum leak NBD. On my way home from lunch one day it just completely sputters out and dies. Cranked it a couple times, no start. Checked my relays all are clicking when I turn the key forward. Turns out to be a fuel pump. It wasn't coming on, so I replaced it with a wahlbro 255lph. Primed it a few times to build pressure back into the line, and it fired right up. When I went to take it to work, it started, stumbled and stalled. I cleaned by TB and IAC, Narrowed diwn my vaccuum leak, and fixed it. Car ran great, and felt really solid.

Today I went to work and it literally died when I got there. stalling the same way. However, I did notice when I pushed the rpms over 3k it just ciuldnt get out of its own way. It idles fine when it starts, but if I give it any throttle when driving it jus bogs out. Its essentially stock, CAI, Accufab SBTB, Pro 5.0 and magnaflows. Nothing I can think could create this problem.

Im thinking either a coil, or my MAF is bad. Any ideas/input?

 

[SVT Rob]

Sounds like you're on the right track. Have you had the codes pulled, to see if it's throwing anything in the ECU?

 

[BKMMBA]

Have you checked your TPS?

 

[phinhead34]

I had somewhat of the same issue. My car would run ok at times, and I would have starting issues at times. After about 4k rpm it felt like it would hit a wall. Checked my fuel pressure, and I was losing some pressure. Pulled the fuel pump assembly and had two holes in the fuel lines from the pump to the hat. Replaced it with a Walbro unit. Car ran perfect and would start immediately. All the components in there get kind of brittle.

 

[jj98cobra]

The funny thing was that before all of this it was throwing a System Too Lean (Bank 2) but it went away as soon as I replaced the battery. I pulled my numbers from,my scanner Abs. TPS was 17.6 @idle. MAF is at .64. And I replaced everything inside the basket when I did the pump.

 

[snakeconvert98]

I am having somewhat the same issue , when mine is warmed up to normal on a hot day (won't do it when cold or below a certain outside temp like 75* ) if you try to run the air it slowly loses power to a point of not even pulling a 5% grade without down shifting , even then it will not rev past 2000rpm ! If you don't run the air it will run fine till you get after it , then it is a crap shoot as to where the rpm will limit itself , sometimes 2000rpm , sometimes 5500rpm or in between it will just fall on it's face like you shut the ignition off !

I had the alt. checked , good , battery , good , changed out coils with known good factory ones , no difference ! Even had the same code as yours (bank 2 to lean) , had them cleared , never returned . I am starting to believe it may be the cats stopping up ! Next on the list is to clean the MAF cause i have read that if oil from the K&N gets on the filiment it will do crazy things , really starting to get on my nerves . When it cools off it runs like a scalded ape till it is at opperating temp again !! We need help !!!

 

[jorgegt500]

im kinda having the same problem here i replaced alot of parts trying to figure it out. coils,wires,tps.maf,egr,02 sensors ,injectors,fuel pump, fuel filter, im still lost on what it can be !:??::??::xpl:

 

[jorgegt500]

try deltelting the imrc if you still havent thats what im doing at the momment using mmr delete plates

 

[snakeconvert98]

try deltelting the imrc if you still havent thats what im doing at the momment using mmr delete plates

That dosn't make sence on mine unless it is the imrc controller cause it only does it when hot ! Then again , couldn't be the controller either cause it dose it below 3200 or 3400 rpm what ever rpm they open at !

 

[jorgegt500]

mine wherent opeing up and they had alot of carbon builod up. but yea ur probally right

 

[jorgegt500]

plus there kinda of a deisgn flaw from ford all they do is build up carbon

 

[jj98cobra]

IMRCs work fine before this. Cant get the rpms high enough to see now. It really feels like its a bad coil, or its sucking too much air.

 

[jj98cobra]

Has anyone thought to change their ETC sensor?

 

[jorgegt500]

any luck yet man? whats etc sensor?:smmon:

 

[Spiney]

We bought a 96 SVT Cobra last July with 38k miles. Always garage kept and well maintained. It started acting very similar about 10 minutes after we bought it and several times after. What I found was the car had a superchip installed on the ECM. The chip was not seated properly and the contents had corroded. I cleaned the contacts and reseated the chip and it's ran great ever since. Now you may not have a modded tuner chip on your ECM, but perhaps the connection to your ECM needs cleaned. It's located insides the passenger kick panel. Just a thought. Also could have a bad ground connection off the battery. Good luck. Spiney-Dave

 

[Bad03gt]

Sounds like the imrc are sticking

 

[jj98cobra]

any luck yet man? whats etc sensor?:smmon:

Been working a lot lately. Gonna pull some more numbers on monday. ECT is your coolant temp sensor. If its running good cold and choking when its warm that would be something to check out. It wont really register anything wrong when its cold IMO, because its not at operating temperature.

Mine is cutting out cold too. So idk... =/

Sounds like the imrc are sticking

Im not even close to their operational rpm range. Im talking <2000rpms. With no difference if I stomp the throttle, or feather it. Not to mention they work fine.

 

[jorgegt500]

well figure this out !

 

[snakeconvert98]

We bought a 96 SVT Cobra last July with 38k miles. Always garage kept and well maintained. It started acting very similar about 10 minutes after we bought it and several times after. What I found was the car had a superchip installed on the ECM. The chip was not seated properly and the contents had corroded. I cleaned the contacts and reseated the chip and it's ran great ever since. Now you may not have a modded tuner chip on your ECM, but perhaps the connection to your ECM needs cleaned. It's located insides the passenger kick panel. Just a thought. Also could have a bad ground connection off the battery. Good luck. Spiney-Dave

Was just thinking today that while at the show tomorrow i was going to pull the kick panel to see if it had a aftermarket chip of some sort , must have read your mind haha , the reason for my thought was different though , my car dosn't have a rev limit , or at least none like any other car i have ever seen , first time i ran my car on a track it went past 7,000rpm pretty quick ,where are they suposed to limit at ?

I did check the IMRCs yesterday by hand and they are NOT stuck , they open freely and close freely but it will make no difference whatsoever from 3,000rpm to 3,500rpm just a steady pull all the way through,,,,,, shouldn't there be a difference when they open ? There is on a buddys 96 , you can feel when they open . I will post tomorrow if there is a chip , cause i will pull it if possable to see if it makes a difference .

To the OP , sorry if i am highjacking , just would like to know what our problem is and help each other if possable .

P.S. Mine will do it also below 3,000rpm if it is really hot outside, with the air on it is worse though .

 

[jorgegt500]

mine works allright when it colds but still cant go past 3500rpm we are on almost the same page here . have you checked your fuel filter aand fuel pump also 02 sensors can make your car run like poop if one of them is bad cause thats what reads your cars air fuel