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Re: Steering/Running Rich

> Greetings,

> > > > I recently purchased a 1987 GMC crew cab R2500 7.4L, auto. > > > > It has several issues: > > > > 1. When I turn to the left the power steering works fine. > > About half the time I turn right, there's no power steering. > > It doesn't make any groaning sounds, just very hard to turn. > > Fluid is full. > > > > 2. The truck runs rich. Black smoke, exhaust smells like gas. > > It's supposed to have recent tuneup. I just bought a new O2 > > sensor and will install it today. > > > > 3. It has a cracked exhaust manifold. Is it repairable or should > > I find a different one? > > > > 4. The title says it's a R2500, but I've seen mention of C2500, > > R2500, V2500, and K2500 when looking for parts. Anybody > > know what the differences are? > > > > Many thanks, > > Roger Hill > >

I installed a rebuilt gear box and pitman arm yesterday, steering problem is fixed. Thanks Scott. I still have the runnung rich problem though. It only smokes black at after its been sitting for a few minutes. No black smoke after driving for a few miles. There may also be a little bit of surging going on at highway speeds. I'm thinking fuel pressure regulator. Any ideas? Anybody have any experience with the aftermarket regulator repair kits?

Thanks, Roger

Reply to
Roger Hill
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What type of fuel system does it have? TBI? And could you explain exactly what the problem is with the black smoke. After sitting when warm? overnight? Both? ect.

Reply to
Scott M

It's a TBI, smokes black anytime after it's been sitting, sometimes after driving around town. When you rev the engine, you get black smoke. The only time it doesn't smoke is after highway driving.

Thanks, Roger

Reply to
Roger Hill

Have you fixed the manifold or replaced the O2 sensor yet?

Sam

Reply to
GaWd

The O2 sensor is on the other exhaust manifold, so I wasn't sure if that was the cause of the rich condition. Although it is a interesting idea.

Thanks, Roger

Reply to
Roger Hill

If you can actually see black smoke comming out of the tail pipe while driving down the road it is WAY rich and there is no way the O2 is the cause. It is probably junk by now though. I would look closely at the MAP sensor and its hose. You can even try running the truck without it plugged in (electrical plug not hose). That will put it into limp-in mode and it will run ok(the ECM will know not to look at the MAP). If it runs better without the MAP plugged in then that is your problem. Only plug/unplug with the key off.

Reply to
Scott M

Agreed. I'd look at the TBI...another poster, DJHATT had some of the same problems and it turned out to be a TBI problem.

Sam

It is probably junk by now though. I would look closely at the MAP

Reply to
GaWd

I finally got around to working on the truck again.

I unplugged the MAP sensor, it definately make it worse.

I also replaced the diaphram in the fuel pressure regulator, that didn't help either.

Here's the symptom again:

After starting the truck it smokes black bad and the exhaust smells of gas bad. It doesn't matter if the engine is hot or cold. After the truck is driven any distance, no more black smoke.

Any ideas/feedback appreciated.

Thanks, Roger

Reply to
Roger Hill

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