85RX7GS

iTrader: (1)

Whenever I step on the gas (from a stop or while moving) somewhat fast, the car hesitates and from a stop, sometimes stalls. My remedy is to slowly step on the gas and let out the clutch, which works pretty well. BUT...before I had the carb rebuilt, it NEVER did this. I also didn't have a working accelerator pump before the rebuild. Is it possible that the air/fuel mixture screw is off balance? I'm going to try and tinker with it tomorrow, but any help from you guys would be appreciated.

By the way, the rebuild was done by Dave@KDR and I'm using the K&N air filter. Thanks.

diabolical1

iTrader: (3)

did you change your filter before you put the carb back on? well, not only is it possible that the idle mixture screw is off, but that was going to be my first suggestion. how is your idle? and do you get a backfire on deceleration?

85RX7GS

iTrader: (1)

It idles a bit high, around 1k, +/- 100. I've had the filter since I bought the car, ie, before the carb was rebuilt. When I decelerate, it doesn't backfire like a piston engine does with a stuck valve, but it doesn't exactly decelerate perfectly smooth.

cletus

This could be what I have dealt with on mine. It was basically running way too rich at idle and dumping too much gas in basically mildly flooding it when you stepped on the gas. Try leaning out the idle mixture screw and see if that improves it.

diabolical1

iTrader: (3)

change the filter before going any farther ...
however, it does sound like a mixture problem, so try adjusting it.

Maguire

iTrader: (1)

Whats is backfiring at deceleration a symptom of? Can it be caused by anything besides bad trailing timing, and leaky exhaust?

jeremy

iTrader: (1)

leaky exhaust. if you have a gutted cat then remove the airpump and it will mostly stop. also ask in your own thread .

i'd agree you're running rich then the accelerator pump is causing an overly rich mixture.

Maguire

iTrader: (1)

sorry, i didnt mean to steal the thread away.... gosh. :P thanks though. Thats all on my long list of things to do.

REVHED

Popping on deceleration usually indicates a lean mixture.

85RX7GS

iTrader: (1)

Too rich? Hmm...I thought I was running too lean...huh

Could it also be that I'm getting too much air for the air/fuel mixture?

Regarding the flooding issue...sometimes, the car seems like it's being choked, kind of like something is holding it back. Usually, I just rev it pretty high the next time I shift and then it's fine for a while...too rich, right?

wxdoc

I've been having similar problems with my 83 GSL. Turned out it wasn't the carb at all - the catalytic converter was clogged and it was only 4 years old. When I had it replaced 4 years ago (due to failing an emissions test) I was having similar acceleration/deaccel symptoms. Might be worth checking into.

Blitz0309

Maguire, you don't happen to drive a black gsl do you?

damon

I was having the same problem as you and I got it fixed last night, I stepped up me fuel pressure regulator and all is good

peace

jeremy

iTrader: (1)

i didn't say backfiring was from lean or rich mixture. it matters not anyway. its from extra fuel moving through the system and firing off in the exhaust due to supplied oxygen (airpump) and ignited usually by a hot spot such as a hole.