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Discussion Starter · #1 ·
got my car running just 48 miles ago and now the
SOB sounds like a diesel just siting there idiling

any idea why it sounds like it does.
it's warmed up and has oil pressure

and for some reason seems to stall out about 5 grand.

any sugestions would be helpful

jesse75z
 

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Discussion Starter · #2 ·
Sounds like you had a valve let loose and is knocking around in there. Maybe the valve keeper came out or broke valve spring. I'd pull the valve cover first. Also could be you had some foreign object get inside a cylinder and the piston is pumping it. Take a magnet and fish around inside the cylinder chamber via the spark plug hole. Good luck. Let me know.
 

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Discussion Starter · #3 ·
> got my car running just 48 miles ago and now
> the
> SOB sounds like a diesel just siting there
> idiling

> any idea why it sounds like it does.
> it's warmed up and has oil pressure

> and for some reason seems to stall out about
> 5 grand.

> any sugestions would be helpful

> jesse75z

On my ZX, it had oil pressure, but still no oil going to the cam. The oil passages were clogged, and the oil was going through the valve that relieves exccess pressure. A hint that this is happening would be if your oil pressure stays all the way up when idling. I would pull the valve cover off and look for any wear spots on the cam, or a lack of oil on it.

I also had a problem with mine loosing power at around 4000-5000rpm, turned out to be the alternator not putting out enough voltage. Changed alternators, and the problem was solved. I think that it couldn't supply the fuel pump enough power to keep up at high rpms. Try accelerating past 5000 pushing the gas peddle only half way or so.

Good luck, Leslie...
 

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Discussion Starter · #4 ·
> got my car running just 48 miles ago and now
> the
> SOB sounds like a diesel just siting there
> idiling

> any idea why it sounds like it does.
> it's warmed up and has oil pressure

> and for some reason seems to stall out about
> 5 grand.

> any sugestions would be helpful

> jesse75z

I would definitely NOT run it in this condition! I had the same symptoms (more-or-less) just after a bottom up rebuild and it turned out to be two things. Foreign objects in the cylinders (that was a machine shop F$$k-up), and also bad gasoline that gummed up the intake valves (my fault).

First thing I would do is take off the valve cover and see if the lash pads are all still in place. Then I would do a valve adjustment. If you didn't tighten down the rocker towers they may have dropped enough to cause the cam to slap the rockers as it makes contact (making the diesel sound). This could also cause your engine to not rev well over 5000rpms because the valves are not opening far enough. Check the valves for free play by pressing down on them with a big flat screwdriver. They should move up and down freely albeit with a lot of pressure on the screwdriver. My intake valves would go down - hard - but not come back up. A sign that bad gas had built up in the guides and siezed the valves.

Hope this helps,

If you need any more ideas from a guy that's going through this right now, just let me know

Steve G
 

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Mine did this when a rocker arm poped of the valve and rattled against the cam shaft. It was also due to a stuck valve. I put it back on and ran it at low rpm and it loosened up and is fine now. About the revs, if it is fuel injected, it definitely has to have good power, like the alt. has to be pumping out good power. I had a bad one and it would run fine until the lights went on at night and those took too much power, causeing the thing to stutter around 2K. I think that the pump should be okay, but that is also something to check.
Joshua L.
 
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