Have you checked you coil lead,my 93 wouldnt rev up and when i was working on some other problem i saw a lt of arcking from the rubber boot on the coil. Changed wire from distributor to coil, every thing fine now(as i was doing most of the work myself i didnt grt to see the motor when running). When the arcking occurs it screws the computer up.good luck Lumppy

 

it was doing that when i frist got it. If you pulled a wire off one of the pulgs it would arc. I changed the wires and coil. The wires are aftermarket. and the coil i put up there was an accel coil.

 

My God, isn't this car running yet ?

 

Thats how i feel to. Some days it seems to run better then others. It seems to be clearing up. oF COURSE NOW THAT I SAID THAT......

 

Crickey, Breatthee, bout the only thing that has not yet been suggested is to check the tyre pressure of the rear left wheel.

So are you seeing any improvement?

 

34-psi.... Kinda. It seems like it clears up but always goes back to the missing under load.

 

Truth be told. I really ready to spend my money on upgrades not repairs.

 

Dig this. So i had unplugged the O2 sensor to see if that would change anything . The CEL came on of course. and it seemed to run a little better. not perfect but better. all this time i've had the CEL on and didn't really think about it not knowing that by unplugging the O2 sensor closed loop fuel metering is canceled and no dynamic fueling correction is applied to the fuel metering . I cleared the code and it runs like junk again.

 

SINCE YOU ASKED, iLL TAKE A STAB AT IT,, MOST COMMON ISSUE ON STUBBLE THAT YOU PARTIALLY ADDRESSED IS MAFS, BUT NOT TPS OR INJECTORS. YOU NEED TO CHECK TPS VALUES AS A SWEEP WITRH A DVOM(DIGITAL VOLT OHM METER) IF THERE ARE DROP OUT ALONG THE WAY THE ECU HAS NO "ACCURATE" VALUE TO KNOW WHERE THE THROTTLE IS AND THEREFOR SUPPLY THE CORRECT AMOUNT OF FUEL. ALSO THE FUEL INJECTORS ARE A BIG CUPLRIT FOR THIS AS WELL WITH A CRAPPY SPRAY PATTERN AND WEAR OF THE PINTLE. SOOTY PLUGS DEFINITLY INDICATE A FUELING ISSUE AND I WOULD BE LOOKING HARD AT MAFS. TPS. AND INJECTORS. YOU CANT DIY INJECTOR SPRAY PATTERNS OR PROPERLY CLEAN. FORGET THE TANK ADDITIVES AND ONBOARD AT THIS POINT. SEND THEM OUT AND GET THEM TESTED, CLEANED AND REBUIT. THERE IS A GREAT COMPANY AROUND THE CORNER FROM ME THAT DOES THIS AT ABOUT $18/INJECTOR (PLEASE LET CHRIS OR BRAD KNOW I SENT YOU , THEYVE HELPED ME MANY TIMES AND I LIKE TO RETURN THE FAVORS)
WWW.INJECTORRX.COM
FOR YOUR OIL IN THE INTAKE ISSUE, ITS NORMAL..TO A POINT. REPLACE THE PCV AND ADD ENGINE RESTORE PER LABEL INSTRUCTIONS EACH OIL CHANGE. IVE USED THIS MANY TIMES TO GREATLY REDUCE ENGINE BLOW BY AS ITS GREATLY INPROVES RING SEAL. AVAIL AT ANY AUTOPARTS STORE INCLUDING WALMARTS

 

OK. the MAF i replaced with a known working unit, no change. Cleaned and reinstalled the old unit. ( it was newer and remaned from jaguar) I did not test the vales of the TPS. so i can do that. I can have the injectors checked and rebuilt if needs be. I was wondering. Why would the car run better after unpluging the O2 sensor?

 

I dont remember you talking about the 02, but if its lazy/slow to respond (check voltage swing with dvom, should be fairly rapid. That said while its a possibilty for your issue, ive never seen a lazy 02 cause your issue. I think more than likely it to has fallen victim to a rich running engine and has deposits on it. Keep in mind 02 sensors are like spark plugs and slow with time and need to be replaced as a maintenance item, but most wait till failure

 

I have a very similar problem to you
Mine idles fine and goes alright but just on take off there is a slight "dead spot" where it almost stalls. After I apply a little more accelerator I get past the dead spot.
I also had a fair build up of oil in the throttle body I cleaned all that out today.
I had a Fuel Fail 23 code and my car is running rich.
and I get a puff of smoke out the back on start up which might be unrelated
I will be watching this thread with interest and will post anything I find

 

OK. so i took off the idle speed control valve pulled it apart and cleaned it, then i thought to myself that the idle was kinda high. i checked what the idle should be on alldata (800 rpm cold in "N") and set it. it ran like a champ... for like five min. ripoff. So i also took the vacuum line off the fuel pressure regulator. Now it runs almost perfect ( about 80%) not really backfiring though the intake anymore, has some power... i thinking thats it fuel pressure but i have no way to check. there is no fuel leaking from the regulator.

 

You need to check and if it run better unhooked its running richer, and popping in the intake is from a lean mix. So unhooking run rich and no longer pops. I think youre just masking the issue. I had to take old fuel lines and make a inline adapter to run fuel pressure tester. You need to check with it running, you cant dead head the fuel and expect know anything accurately

 

45 PSI. when i rev the motor up quickly is starts to drop.

 

sounds like fuel pump?

 

After all this time I would have thought the problem would have been tracked down by now. It does seem to be fuel, i.e. OK at tickover, but any demand causes failure. I think it might be worth checking the fuel tank pick-up filter. I had a similar problem with my old XJ6 of 1980 - blocked intake filters in the fuel tanks- pump could not suck the petrol through except for tick-over when fuel demand is minimal. These filters are gauze type to prevent corrosion particles from wrecking the fuel pump.

 

I'll give that a shot. maybe replace the fuel pump as well but if that don't work i'm gonna have to get rid of it.... breaks my heart. i think i've replaced everything i could other then the injectors. oh well. wish me luck.

 

Figured it out. There was so mush junk in my fuel tank it was plugging up the filter that it wasn't getting any fuel. drained the tank, cleaned it out, and put a new pump in cause i thought it was a good way to get rid of another hundred dollars. But she runs like a dream. Thank for the help guys. now i got to figure out how to get to take off better but that will be a new post