93 festy still not running right please help

[redrocket81]

93 festiva not running right, ill be driving at 55mph and all is good then he check engine light comes on and it feels like i lost a cylinder, i push clutch in and rev a little bit light goes off and all is good. It might run a mile aor it could be 1/4 mile and it does it agin. Sometimes it dont do it at all, I have replaced the fuel pump , plugs,wires,cap button checked for vacum leaks,and was told it might be tps sensor not sure what to do..........

[koRnhead]

O2 sensor.....would be my first place to look.

[georgeb]

Do the self-test. Ground the single wire by the booster with key on and count blinks of CEL. Do this before you start throwing money at it.

[jbuck1975]

Do the self-test. Ground the single wire by the booster with key on and count blinks of CEL. Do this before you start throwing money at it.

Can you explain this to a dummy like me?

EVO deck'd out with Bruce Lee

[redrocket81]

ok will do the test tomorrow and let ya know how it turns out.

[georgeb]

Can you explain this to a dummy like me?

EVO deck'd out with Bruce Lee

There's a 3-gang empty connector near the brake booster. There is also a single one next to it. Get a male blade connector and crimp it to a piece of elec wire with an alligator clip at the other end. Attach the blade to the single connector and ground the alligator clip. Turn the key to ON and observe the blinking of the CEL. The long illumination is the first number and the short is the second. It will cycle through all the stored errors then repeat. The Haynes manual has what component corresponds to what code.

[jbuck1975]

There's a 3-gang empty connector near the brake booster. There is also a single one next to it. Get a male blade connector and crimp it to a piece of elec wire with an alligator clip at the other end. Attach the blade to the single connector and ground the alligator clip. Turn the key to ON and observe the blinking of the CEL. The long illumination is the first number and the short is the second. It will cycle through all the stored errors then repeat. The Haynes manual has what component corresponds to what code.

OK thanks. I think I have a little better idea now.

EVO deck'd out with Bruce Lee

[Larry Hampton]

I had the same problem, it turned out to be the O2. I picked it up at AutoZone, Denso 234-1010, also had to pick up O2 socket. Don't remember how much the sensor was, but the socket was $10.49.

[Movin]

If you don't have the haynes just type in the
code and festiva in google , yahoo bing whatever
it should come up..

[georgeb]

Another tidbit from the Haynes manual: After repairs clear the codes by unhooking the neg cable and depressing the brake for ten seconds. Related story: My daughter's '93 BMW has a CEL illuminating. Emissions test looming. Would not communicate with fancy scanner. Found on Google that turning key and flooring gas pedal 5 times will retrieve codes. It worked! Info was not in Haynes or $50 Bentley manual.

[FestYboy]

93 festiva not running right, ill be driving at 55mph and all is good then he check engine light comes on and it feels like i lost a cylinder, i push clutch in and rev a little bit light goes off and all is good. It might run a mile aor it could be 1/4 mile and it does it agin. Sometimes it dont do it at all, I have replaced the fuel pump , plugs,wires,cap button checked for vacum leaks,and was told it might be tps sensor not sure what to do..........

wiggle test the VAF connector while the engine is running...

[redrocket81]

ok what is a vaf ? i also swapped out o2 senser not the problem......will try the other test tomorrow hopefully been really busy....

[windy1]

eratic idyl

engine light on,can be put on a diagnostic machine,at garage. sounds like fuel system put a can of seafoam,in tank. or put in a whole bottle of fuel injection cleaner,every other fill up.or a garage,can do a fuel injection service .engine lights are for a reason. luck to ya,dude.

[georgeb]

engine light on,can be put on a diagnostic machine,at garage. sounds like fuel system put a can of seafoam,in tank. or put in a whole bottle of fuel injection cleaner,every other fill up.or a garage,can do a fuel injection service .engine lights are for a reason. luck to ya,dude.

Yes the CEL comes on for a reason. So you can diagnose it in your driveway and not pay a gangster $80 an hour for bad info.

[FestYboy]

ok what is a vaf ? i also swapped out o2 senser not the problem......will try the other test tomorrow hopefully been really busy....

VAF = Vane Air Flow, it's the aluminum box on top of your air cleaner. with the engine running, wiggle the connector up and down. do this AFTER removing it, inspecting all the pin connections for corrosion and pluging it back in.