2002 4.2L Issues.....
 

To start off, I have searched a lot and came across a lot of answer but I'd like to get a little more info.

2002 4.2L with 142,000 miles

CEL p0171, p0174, p1131, p1151

The owner replaced MAF, IAC, Injector, Air Filter, BOTH Upstream 02 Sensors and issue is still present.

Today I start looking around for vacuum leaks and couldn't find any. While looking around I found #2 spark plug very loose, almost falling out. I removed all 6 NGK plugs and replaced with Motorcraft. I also ran some seafoam in the brake booster line. The idle seamed to smooth out a lot and no CEL. We came inside for a few and then he went to leave and the CEL came on again. P0301, P0316, P1131, P1151. I check all the plugs and wires. Cleaned the codes again and so far so good. I'm assuming the 301,306 might have been a loose plug wire.

That leaves me still with the P1131, P1151 codes. It seams that the intake gaskets and isolator bolts are the issue.

I have 1L3Z-9H486-AA and 3F2Z-9S479-AA for part numbers.

Do I need 6 gaskets or do they come in a 6 pack? Do I need to order 8 bolts or do they come in a 8 pack?

What about the big gasket for the upper to the middle intake???

Thanks
Wayne

Well i ended up ordering 6 new lower to mid intake gaskets, 8 new isolator bolts, 1 mid to upper intake gasket, fuel filter and a set of plug wires. Hope that fixes things! Ill report back next week once i install it all to let you know if it fixed the issue.

Wayne

Wow. Too bad the owner started firing away with the parts cannon before doing anything else...like googling this stuff.

Anyway, been there, done that with these gaskets. The P1131/1151 will clear when the gaskets are done. I imagine in my case, it was the isolator gaskets leaking air into the engine like sieves that tossed those two codes. Be sure to line up that big gasket with the "arrow" where it belongs in the intake.

Other than the reaching behind the engine under the cowl, it's not too bad a job. Aside from waiting for parts to come in, that is...

Take a look at this.

http://sites.google.com/site/fordf15...p0174fix/Home/

Been there done that, it's been over 100k miles since I did mine and still no issues.

Also spend the extra money for the Ford isolator bolts and follow the torq sequence.

Just to give an update. After changing the gaskets and bolts truck is running perfect and CEL hasnt come back on!

Wayne

Glad you got it!