1996 cobra it sputters only between 3k-4k rpm?? - Northern California Ford Owners

This is topic 1996 cobra it sputters only between 3k-4k rpm?? in forum Tech Talk at Northern California Ford Owners .

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Posted by 1SICK86 (Member # 8619) on :

So yes my cobra sputters some time back fiers between nd only 3k-4k RMP also dose it mostly when it's cold so far I was told to replace the spark plugs nd to gap them at .054 nd nd did not fix problom also it is running real rich I can smell a lil bit of raw fuel oh any info can help me or if this has happend to any one else Thanx for the help caford ill keep up with What i i do to the car.

Posted by dohcfox (Member # 12829) on :

Any check engine lamp codes? That's the rpm that the imrc should open.

Posted by 90 7up lx (Member # 10304) on :

Msd coil packs?

Posted by 1SICK86 (Member # 8619) on :

We'll I have no check engine light what's so ever I have ran a scanner several times nd have stock motorcraft coli packs but no I have s good question for since I'm new to the moduler motets what is the imrc nd what can I go to fix problem would take any help u20949509405

Posted by 90 7up lx (Member # 10304) on :

Imrc are Intake Manifold Runner Controls.....96-98 cobras have them...the cylinder heads have two intake ports thus they are called B heads...between the heads and intake manifold their is a plate with a set of mini throttle bodys for each intake port. Only one intake runner is open until the vehicle reaches 3,200 rpm then the second runner opens up..the issue is that most of the time these runners get gunked up with oil and sometimes get stuck or the imrc module is faulty and dosent open them up...its a very common issue with these engines.....seafoam helps out a bit but you wont know how bad it is untill you remove the intake and thoroughly clean the intake runners out...

I have a set of delete plates and a short runner intake if intrested..

Posted by 90 7up lx (Member # 10304) on :

Also what kinda plugs did you use? 91 octane right...

Posted by 1SICK86 (Member # 8619) on :

Yes I use 91 octan and I just put on brand new motorcraft spark plugs platinums gaped at .054 bt I was considering doin the seaphon bt I was woundring if I put thro my throttle body or wer dose it go thro to clean it up

Posted by 70stang351w (Member # 9948) on :

1/2 can seafoam in brake booster while car is running let it suck half a can of it in slow not in one shot hook brake boost back up let run for a few sec then cut for 15min then drive around till no more white smoke comes out exhaust.

the brake booster method easier to do with 2 people.

i used to buy 2 cans at a time 1 in the gas tank and the other one was split for the oil and the brake boost method. did this both for npi 2v and 97 cobra motor(my cobra motor didnt have the irmc plates either so wasnt an issue for me.

[ 2014-06-06, 06:20 PM: Message edited by: 70stang351w ]

Posted by dohcfox (Member # 12829) on :

There is no vacume line on the brake booster on a cobra..... Take the line off right on top of the intake on the drivers side. It connects to the PVC valve. Squirt it thru there, I'm not sure I would suspect this to fix your drive ability issue Ither. When the computer commands the imrc valves to open it also ramps up fuel volume dramatically to accompisate for the extra volume of air the engine is about to Ingest. I would suspect a fuel delivery issue, don't go throwing parts on til you verify the cause of this comserm. Use a fuel pressure gauge. You can rent ken for free from autozone. Hook it up to the fuel rail shraider valve. Located on the pass side front of the engine. Pin the hose under the back of the hood and clip the gauge under the wiper blade. Go drive the car. Fuel pressure should be between 34 and 41 psi varying with throttle load. If you see pressure die off when you get the sputter suspect a weak pump plugged filter or crimped off fuel line.

Posted by 1SICK86 (Member # 8619) on :

Thanx guys I'm going to get on it tomarro morning nd see what's up nd ill get back to you guys with the diagnostics .

Posted by 70stang351w (Member # 9948) on :

quote:
Originally posted by dohcfox:
There is no vacume line on the brake booster on a cobra..... Take the line off right on top of the intake on the drivers side. It connects to the PVC valve. Squirt it thru there, I'm not sure I would suspect this to fix your drive ability issue Ither. When the computer commands the imrc valves to open it also ramps up fuel volume dramatically to accompisate for the extra volume of air the engine is about to Ingest. I would suspect a fuel delivery issue, don't go throwing parts on til you verify the cause of this comserm. Use a fuel pressure gauge. You can rent ken for free from autozone. Hook it up to the fuel rail shraider valve. Located on the pass side front of the engine. Pin the hose under the back of the hood and clip the gauge under the wiper blade. Go drive the car. Fuel pressure should be between 34 and 41 psi varying with throttle load. If you see pressure die off when you get the sputter suspect a weak pump plugged filter or crimped off fuel line.

^^ his correct my bad got my motors mixed up

Posted by WILDMAN97 (Member # 9138) on :

If the IMRC valves are stuck open or close even for a brief time a code will be stored on the ECU. So if that were an issue it "should show". Sea foam will do ok job at best, the only real way to clean them is to pull them out and do it by hand. The IMRC's get gummed up but the real problem is the intake valves, clean them by hand. Here is a pic of mine with 68k on the clock.

I cleaned them both by hand but didn't take any after pics.

[ 2014-06-11, 10:20 AM: Message edited by: WILDMAN97 ]

Posted by 70stang351w (Member # 9948) on :

or you can delete them; found this gives you a how to and explanations of why or why not to. Mine already had it done to the motor so couldnt tell you the difference with or without. .

http://www.modularfords.com/threads/138793-IMRC-Deletes

Posted by 1SICK86 (Member # 8619) on :

Thanks guys haven't got to the sea foam yet but as I can see yours with 60k looks bad mine has 160k so must look horrible Im going to get on it ASAP it's just been to hot out here in the valley Thanx cafords ill get back to you guys with details

Posted by WILDMAN97 (Member # 9138) on :

Do a google search on cleaning the IMRC's and valves. A few good threads are out there.

Posted by SIC9250 (Member # 8216) on :

Imrc plates and b heads FTL..hate the drama they caused my car,all deleted now..

Posted by 1SICK86 (Member # 8619) on :

Thanx guys put some deadpan in it runs good now but still think I'm going to do the delete just wen I have a lil more time Thanx cafords ill let u guys kno when I do the delete

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