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-   -   Gsl se idle problems/ running rich (https://www.rx7club.com/1st-generation-specific-1979-1985-18/gsl-se-idle-problems-running-rich-928283/)

jdm12a 10-26-10 01:57 PM

Gsl se idle problems/ running rich
 
Okay so i have searched last night and today and have not found anything that fit my specific problem and tinkered with the car and cant figure it out so maybe you guys can help.

Car is an 84 gsl se 99k. Has a racing beat full exhaust and a cold air intake.

On a cold start it bogs down and dies if i dont feather the clutch for the first 20 seconds or so. The it idles rough until the car warms up (2min) then perfectly fine idle after warmed up. When i floor it and really run thru the gears it reeks of gasoline afterwards now too.

Test drove the car before i bought it and it ran fine. Started up fine and didnt do any of this and did not smell of gas thru speed runs. Drove the car for 30 min then took it back to check compression and i did not take the fuse out for the fuel pump when i cranked it so could this have fouled the plugs up completely maybe? They didnt look that bad to me when i checked them today and they were all getting spark.

thanks guys, please help me get my dream car kicking ass again.

ratboy 10-26-10 02:48 PM

http://www.nellump.net/peri/epi/firs...gslseIdle.html

this is the best writeup I ve seen for solving SE idle problems. I havent worked through this in a while (see, it works!) but my wild guess would be sticking BAC valve??

jdm12a 11-01-10 11:03 PM

. . . . really people. . . ?

Whisper 11-02-10 04:21 AM

You sure it's running rich and not just a fuel leak somewhere?

There are a lot of threads on GSL-SE rich running troubleshooting. Some are even by me.

Few reasons it might run rich:

Bad ECU - unlikely
Fuel injectors are old and spraying too much - also unlikely but possible
Fuel pressure regulator bad, causing fuel pressure in the rail to be too high - unlikely
Some sensors are bad - intake air temp sensor on the plenum or the coolant temp sensor in the water pump - possible
Airflow meter bad, loose wire somewhere sending bad signal - possible
O2 sensor bad, maybe fouled up by the fuel dumped into exhaust when you did your test - possible, though not likely to affect mixture during hard driving, it's mostly used for cruise and idle, I think.

I don't think spark plugs would be an issue. If they're firing strong enough to ignite the mixture then they're fine. Make sure you put the plug wires back on correctly, though, so they're firing when they should.

I'd start with the temperature sensors. They're responsible for proper warmup and mixture. Also check that your TPS is set right.

djs2571 11-02-10 11:41 AM

horribly leaky injectors, possibly the gasket / o-ring around the injector blowing fuel out or sucking air in - causing a rough idle.
The cold start system has a cam which opens the throttle until the coolant is at 72F, a low idle when cold could cause rougher than normal running.
It's likely that there's a leaky injector, but that usually causes a flood condition, and not just rough idle.
The TPS is one part, and there's also an adjuster pot for the fuel mixture, though I don't recall this making much difference when I messed with mine.

Make sure you identify where the fuel leak is - the fuel rail has a pressure regulator that likes to leak and catch cars on fire - MAKE SURE THIS ISN'T THE PROBLEM.

Whisper 11-02-10 12:35 PM

It's not the fuel pressure regulators that leak, it's the pulsation dampeners, but I think it's mostly on second gens.

The mixture adjuster is for fine tuning, makes a difference of maybe couple hundred RPM at most.

I imagine if the injector gasket is blowing fuel out/sucking air in it would cause a lean condition, rather than rich. Unless of course he isn't running rich and just has a fuel leak. That can usually be determined by locating the fuel smell - is it in the engine bay, or is it out of the exhaust.

trochoid 11-02-10 02:06 PM

Are you setting the cold start system before starting? It doesn't set itself, you have to push the accelerator pedal to the floor, once, to set it. The SE pulsation dampeners are just as failure prone as the FC ones. Any time there is a strong fuel smell, that's the first part to check. Look for a brown residue buildup around the injectors and PD. That's a fuel leak tell.

djs2571 11-03-10 05:54 PM


Originally Posted by Whisper (Post 10299464)
It's not the fuel pressure regulators that leak, it's the pulsation dampeners, but I think it's mostly on second gens.

Yes, pulsation dampener, mis-thinking on my part. Though I had two GSL-SE's and both had a leaky dampener at some point.
BTW my first one that had been beat got pulled apart at ~170k and had some chipped housing edges and that's about it- it was still running fine.
The second GSL-SE I sold with 196k on it with no other engine work, the new owner killed it though -think it had an apex seal go on it. Though i'm guessing that's cause he didn't let it warm up before revving it up.

If you get one, have the owner take it out with you in it - how they drive is a clue what the engine has been put through.

jdm12a 11-15-10 12:33 AM

awesome guys thanks, i have the next 2 days off so im gonna look into ill keep you posted

jdm12a 11-23-10 12:15 AM

alright so i checked that baby over about 3 times and i couldnt find fuel spraying anywhere? is there another means to test it or does that mean its safe?

any other ideas on what could be causing this?

jdm12a 12-11-10 07:53 PM

alright so i changed out plags and wires and it is still running rich and smells like gas bad under WOT


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