Car only runs when gas is applied..

artrenee10

Older...wiser...and broker...
Joined
Jul 23, 2002
I thought it was no spark, but then how would the car run unless gas is applied? So that rules that out...MAF Sensor is brandy new....new coil pack and ignition module. Fuel pressure also looks good. Im thinking Vacuum Leak but where? I checked for vacuum not quite sure if I am going about the right way. On the scanmaster, the BLMs are locked in 128 but when it was running, I could not adjust the IAC down either. The CC are at 0 always. Any hints..lots of ?'s and I am sleepy:eek:
 
But the TPS is w/in spec....set at .44 at idle....engine cold....still don't get it know its something relatively easy....
Thanks SoCal Gn.....
Also when the engine is cranking...I do get a SES light and the voltlight comes on as well....
 
CCs at 0 indicate a dead O2 sensor (no activity). If it runs off idle, there's only so much to check; TPS, IAC, MAF, vac leaks. (I think that's it)

make sure you reset the ECM, also.

Check for leaks at the throttle shaft, on the throttle block on top of the TB, and the various lines behind the doghouse.

Lights coming on during cranking is normal.

How was the car running before?
 
It was running but, the car had falling fuel pressure at Idle until I cut the pulsator and replaced the fuel injection hose as well.....otherwise than that it would at least start....now it just cranks.....:(
 
It was running but, the car had falling fuel pressure at Idle until I cut the pulsator and replaced the fuel injection hose as well.....otherwise than that it would at least start....now it just cranks.....:(

So I understand- before you monkeyed with the pump, fp would drop at idle, correct? How much of a drop?

Is the pump stock? Hotwired?
 
So I understand- before you monkeyed with the pump, fp would drop at idle, correct? How much of a drop?

Is the pump stock? Hotwired?

It would start off at 40 (as I set it) and then the longer it ran it eventually would drop to about 20 at Idle, and then I would shut it down....I tried a new FPR same result, until a mechanic buddy told me about the pulsator....pulled the pump and the hose was cut right where the pulsator was. Cut the pulsator installed new hose, and now it drops to about 20 PSI but that's after about 30mins-1hr or so...Installed new coil pack/ign module/fuel filter has less than 100 miles....still nada...but Im thinking my IAC motor is dead b/c no matter how many times I turn the screw clockwise to raise it...the numbers will not rise...TPS is within spec/and no Vacuum Leaks that I can see or hear...and when I give it gas...the motor is strong like always...but as soon as I let off....pow....dead car...battery is fully juiced too....
Steve Chambers
 
It would start off at 40 (as I set it) and then the longer it ran it eventually would drop to about 20 at Idle, and then I would shut it down....I tried a new FPR same result, until a mechanic buddy told me about the pulsator....pulled the pump and the hose was cut right where the pulsator was. Cut the pulsator installed new hose, and now it drops to about 20 PSI but that's after about 30mins-1hr or so...Installed new coil pack/ign module/fuel filter has less than 100 miles....still nada...but Im thinking my IAC motor is dead b/c no matter how many times I turn the screw clockwise to raise it...the numbers will not rise...TPS is within spec/and no Vacuum Leaks that I can see or hear...and when I give it gas...the motor is strong like always...but as soon as I let off....pow....dead car...battery is fully juiced too....
Steve Chambers

and yeah it is hotwired....Casper's Special...
 
Mine does a similar thing, it only stops when I apply the brakes? Related issue?! j/k
Do you have an inline fuel filter that may be clogged?
 
Sounds like a tired pump if it's not the filter suggestion above regarding fuel pressure dropping, but if it's at 40 while you're cranking then it seems you have another issue. You sure the settings are correct on the translator? Do you have a stock maf you can test with?

As far as the IAC, you would turn it counterclockwise (close the throttle blade) to raise the counts. Clockwise (opening the blade) would make the counts drop because its getting enough air that it doesnt need to move the IAC anymore (as always, correct me if I'm wrong.)
 
:smile:
Mine does a similar thing, it only stops when I apply the brakes? Related issue?! j/k
Do you have an inline fuel filter that may be clogged?

How corny..:smile: I wish it would only stop when I applied the brakes...make this a whole more fun..........
 
Sounds like a tired pump if it's not the filter suggestion above regarding fuel pressure dropping, but if it's at 40 while you're cranking then it seems you have another issue. You sure the settings are correct on the translator? Do you have a stock maf you can test with?

As far as the IAC, you would turn it counterclockwise (close the throttle blade) to raise the counts. Clockwise (opening the blade) would make the counts drop because its getting enough air that it doesnt need to move the IAC anymore (as always, correct me if I'm wrong.)

Im sorry but was there a bad batch of Walbro 340;s that came out?? Im just wondering out loud.....

Well I havesome stuff to double check tonight so I will be busy.....translator settings is one of em......
Thanks All
Keep em comin

Steve Chambers
 
Oh i didnt see you mention you did a pump, I thought u just removed the pulsator and left the pump.

Good luck!
 
Went back and rechecked the wiring on the coil pack ( Im a visual person, I need pictures:) ) came to find out I had the spark plugs wires leading to the wrong coil pack terminals....now the car is running but like crap...still sounds like its three cylinders...
 
if you're 100% sure its correct now, i would still double check it again, otherwise maybe the plugs are toast from the amount of times you tried to run it incorrectly. other than that, ive seen cars (almost) run without the maf hooked up (or bad for that matter.) check the maf plug? maybe swap it out if possible? my car ran like that when my maf went bad, luckily i had a brand new one sitting and took a guess to try it out.
 
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