Bikergems

1982 original cfi engine. Starts ok but rich at idle leaving soot spots on driveway coming out of exhaust while warming up. Clears up after engine is warmed up.
Is this normal?

mikem350

Not normal! Scan for codes, clear up any problems shown by check engine lite. Check for missing/rotted vacuum hoses.

Maybe change spark plugs as part of tune up with wires, etc.

Bikergems

Thanks Mikem350
Not familiar with retrieving codes.
How is this done?
Check engine light is not coming on but it lights up when ignition on then turns off after engine is started.

2TONE82

While not normal, not overly abnormal on the CFI. Probably not throwing codes, yet or check engine light would stay on. Maybe a vacuum line but I'd start with cleaning IAC valves. Each throttle body has one at front of body. You might have success spraying carb cleaner into throttle body (warm car up first) but may need to remove IAC valves to clean. Start here and post if helpful. Other things we can try.

alconk

First off do you still have the cat convertor on the car? Mine does the same thing with no convertor but did help a lot by installing a heated 02 sensor. Also the colder outside the worse it is for me. A convertor will take care a lot of that problem that's why I asked about that.

Bikergems

Everything is original on the exhaust.

Bikergems

Cleaned the IAC valves. They had some buildup but looked good.
Checked the vacuum going to lights and CC. Leaking. Presently hunting down leaks. Plugged vacuum ports and idle was around 700 rpms vs 900 rpms with lines connected.

hugie82

Vacuum leak would be my first place to look. Did you replace the plenum plate silicone with the Felpro gasket?

terry82

changing the cat will help with performance and gas milage. they were bad in 1982.

Bikergems

What is the plenum plate?

terry82

the top of the intake .there are a lot of little bolts holding it down .the tbs are bolted to it.

Red1990VT

Sounds familiar...

My 1990 has the problem of starting, blowing all kinds of black soot into the driveway, and then on warming up, dying. It pressurizes (fuel pressure gauge attached to the fuel rail port) but then drops pressure as soon as the key is turned off. Your 1982 might have a similar problem.

Suggest you try this...remove the air cleaner, turn the key to on but not start, and see if the fuel injectors are leaking any fuel. Listen to be sure the fuel pump pressurizes or check fuel pressure with a gauge. The injectors should not be allowing any gas to drip with the car on but not started.

If there is any gas dripping or running out of either injector, replace that injector(s).

Also, if you have a fuel pressure gauge attached, the pressure should come up when you turn the key on (but not to start) and hold pressure after you turn the key back off. If not, there is a problem in the fuel system.

I troubleshot my 90 to the point of knowing it needs an injector or more. The fuel pump is ok, and the regulator is ok, leaving the injectors as the remaining problem. Can't view the injectors as in the 1982, so I don't know which it is.

My 1982 idles fine but has hesitation problems under load...the subject of a different post.

Good luck, be interested to know what you find.