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Topic: Carbon on rear of car (Read 1441 times) previous topic - next topic

Carbon on rear of car

Hey guys, I've been having a problem with carbon bein spit all over the rear of my car.  All the way up to the back of the trunk, to the license plate, to the rear bumper.  Its just a bunch of ugly black dots all over the place, and only on the rear of the car.  Not on the top of the trunk lid or rear quarter panels.  I have to scrub it off every time I wash the car, and I'm pretty tired of it, nor do I have any idea how to get it to stop.  Any help is greatly appreciated.

Carbon on rear of car

Reply #1 –
Ya running a bit rich?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Carbon on rear of car

Reply #2 –
Quote
Ya running a bit rich?


Better yet...Ya runnin' cats?  Done a compression test recently?
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Carbon on rear of car

Reply #3 –
Yes, I have a stock Mustang H pipe with 4 cats.  Haven't done a compression test, but judging by the runs I had at the track on Saturday, I dont think she's struggling to make power.  It started happening when I got the exhaust done, so I think it's related.

Carbon on rear of car

Reply #4 –
Anybody?  It's really an eye sore...

Carbon on rear of car

Reply #5 –
Run codes, compression test, fuel pressure test, injector leakdown test.  Also, was the H-pipe new?  Used?

Had the same issue with my old red V-6 and it ran dead perfect.  Valve stem seals were the culprit.  Never got around to fixing them.  At it's worst I was blowin a quart every 500 miles or so.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Carbon on rear of car

Reply #6 –
The H-pipe was used.  It had 4 new(er than stock) cats in it from the recall that Ford had a while back.  As for the engine, I know for a fact that the injectors aren't leaking.  The lower intake has been bone dry (unless they leak elsewhere).  We've run codes on it to try to find out what has been causing the bog issue I've had since day 1 with the HO, but not a single code pops up.  When I do a fuel pressure test, what do I need to look for?  Thanks a bunch for your help.

Carbon on rear of car

Reply #7 –
Quote
We've run codes on it to try to find out what has been causing the bog issue I've had since day 1 with the HO, but not a single code pops up


Describe the bog issue.  Part throttle I assume from the time posted?

Quote
When I do a fuel pressure test
  Vacuum line off the pressure with a stock regulator should be around 40 PSI @ idle.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Carbon on rear of car

Reply #8 –
Quote from: kingcars;204419
The H-pipe was used. It had 4 new(er than stock) cats in it from the recall that Ford had a while back. As for the engine, I know for a fact that the injectors aren't leaking. The lower intake has been bone dry (unless they leak elsewhere). We've run codes on it to try to find out what has been causing the bog issue I've had since day 1 with the HO, but not a single code pops up. When I do a fuel pressure test, what do I need to look for? Thanks a bunch for your help.

You Won't see a bleeding injector on your lower int.It' not like gas runs wild!.Your really not saying everything your doin to your ride,performance wise if any?
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Carbon on rear of car

Reply #9 –
Ever since the HO conversion, the car has had an intermittent (doesnt happen every time) problem.  It will idle rough, then at launch it will bog a couple of times (and with the worst bogs, it will make a backfire pop), then go.  If anyone has ever driven an old American V8 when its cold and it just doesnt quite want to get goin from a stop, thats exactly what my car does.  I had posted about this a while back, but nobody can figure it out.  It never throws codes, runs great, doesn't leak, etc.  It's just that one weird issue.  And under full throttle, it does not bog (but the rough idle is still there).  My dad and I suspect fuel pressure to be the issue, but we need to get the right fitting so we can test it.  The weird part is how it runs PERFECT sometimes.

As for the injector leak, the only reason I said that is because when we first started up the HO, there was a broken injector O ring and it leaked all over the lower intake.

Performance-wise, everything is listed in my sig.  The timing is at 14deg right now, but it hasn't helped nor harmed the problem at all.  I've had the car at 10, 12, and 14 and the problems havent changed.