New guy with a Cobra that doesn't idle

[Stockwell45]

Hi, I'm new to Cobras and Fords as well. I picked up my supercharged 98 cobra about a month ago, it's been running great until tonight. I changed the plugs and wires earlier today, and it ran beautifully afterwards. I let it warm up for about 15 minutes, then drove it around the block for maybe 10 minutes. Went WOT a couple times in 1st and 2nd, no problems. Once I got to the highway, I went WOT and it suddenly seemed to fall flat on its face, it wouldn't rev past 3k and if I pushed in the clutch it would die. I managed to get it home by keeping my foot on the gas. Now that it's in the garage I can keep it running if I stay on the gas, but it will die instantly if I let off and I smell raw fuel. It doesn't miss, no weird sounds or vibrations. I checked all vacuum lines, connectors and everything seems fine. all the plug wires are still firmly attached. Any ideas? I've done a ton of searching and have come up short besides some info on the IAC. I'm also smelling some gas in my oil, not sure if this is related. Any help would be great.

And here's some pics since everyone loves those.

 

[MustangMatt77]

I'd try whacking the IAC with the big end of a screwdriver or remove and clean with brake cleaner.
Also I know you said you looked for vacuum leaks, check with carb cleaner, also look carefully, some hoses can actually collapse and still not cause a vacuum leak, they just rob the engine of the vacuum it needs. Happens a lot on hoses with u shaped curves or high suction.
Not throwing any codes? Never know, the dash light for the CEL might be burned out, check at start up.

 

[04DeadShort]

Check you mass air too. You have a draw thru setup and depending on how your boost bypass it piped in, you could have blown some trash back in to the mass air. How much psi you running?

 

[Stockwell45]

I removed and cleaned the IAC, no luck there. No codes either, I checked that this morning.
I'll check the mass air when I get home. I'm only running about 6 psi of boost.

 

[04DeadShort]

I got some kind of residue on my mass air one time and it would cause the car to fall flat. Cleaned it with contact cleaner and it was fine.

 

[cobrarob2345]

what kind of spark plug wires did you use

 

[Stockwell45]

I Took out the MAF sensor, and gave it a good cleaning. That did the trick, it runs great now. Thanks everyone for your help!

 

[cbrown9064]

Sweet! Glad when it turns out to be something easy!

 

[SNAKEYE]

Don't over-oil the air filter.

 

[jmsa540]

I Took out the MAF sensor, and gave it a good cleaning. That did the trick, it runs great now. Thanks everyone for your help!

Make sure to disconnect the negative battery cable, so the PCM can relearn the new driving since the MAFS has been cleaned.

Also, I'm on my third modular motor and I always make it a point to change out the IAC's.