Can anyone help me with a question that I have on an 85 Iroc?
It has a Tuned Port 305, rebuilt 20,000 miles ago. It has T-tops, but I
don't ever take them out anymore because the exhaust smells. It smelled
before the engine was rebuilt as well, but was not the reason for the
rebuild. It is choking me out. I just drive it around town. When I do
get on the freeway, and am driving at a constant speed for 10-15
minutes, the check engine light comes on.
It gives me an EGR error. This is the second EGR valve that I have had
in it, and I still get the error. The second EGR was out of an 86 parts
car that I had. Could it be another bad EGR, or is there something else
that is causing it to run rich? The timing was set by a local tune up
shop. When I tried to time it, the timing marks were off by about 90
degrees. Also, the cat seems to have been hollowed out before I got the
car. I have planned on replacing it with a high flow. Would that
contribute to the problem? Could my fuel pressure be too high or too
low? It has the factory non adjustable pressure regulator and a fuel
pump that is at least 4 years old.
Also, the computer was replaced with a new factory one. It has K&N
filters and a flowmaster. Any help is appreciated. I am trying to find
the problem without spending every cent I have. My wife won't drive in
the Iroc with me anymore, we always have to take her jeep. This is
It's extremely common that the egr passages will be clogged. You'll need to
remove the plenum and the runners and clean those passages out then try to
clean out the EGR passage in the intake. It'd be best if you could take the
intake off but you can do it without removing the intake, it's just more
time consuming and harder to do but it's do-able.
You might run some BG cleaner in it.. It's supposed to dissolve or soften up
any crap that's in the EGR passages but if it's clogged, it won't really
You should be able to check your fuel pressure but it would be unlikely that
it's *too* high or the engine wouldn't run very well. If the diaphram in
the regulator is punctured, then raw gas is getting sucked into the vacuum
system which could cause problems. The fuel pressure regulator just helps
to maintain constant fuel pressure across the injector. If fuel pressure is
higher at some points, the computer will compensate by reducing or
increasing the injector duration.
The best thing to do at this point is to go and get the exhaust checked. If
you're smelling raw gas, then you should already have a good idea but if
it's just a smell, you need to figure out what you're smelling so you can
limit the possibilities.
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