Ok, he is the story. A guy from AL bought this vert from chattanooga and brought it to his brothers house in tn. When he bought the vert he was told it needed a fuel pump. He bought the car, towed it to his brothers house so they could work on it and then he could drive it home. Well he is still at his brothers house since they can't get the car to run right. He found me (I live 4 mins from his brothers house) and asked me to come look at it.
Well today I spent a few hours over there looking everything over, adding 3 grounds to the car (battery to shock tower, battery to motor, and motor to body. One will be going to starter to body soon) and checking out some other items. So here is the deal,


91 Vert Na Auto. In park and idle she seems good. Starts right up and idles fine. Put it in drive and give it a little gas and she fall on her face. I drove it and it would not go over 20mph, so I tossed it in neutral and still would not let me tach it out.
We swapped out the air flow meter, because he said it seemed to be sticking, but still the same problems. We added those grounds (needed it anyhow) and still same problem.

The fuel pump has been replaced with a new one and still same problem. We are getting fuel at the motor, and we are getting spark.
Have not tested the compression, or the fuel pressure. We also have not dropped the exhaust at the 1st cat to see if the cats are plugged.
We did however find the fuel pump yellow plug on the passenger side fender to be jumpered but the car runs the same with it jumpered or not.

Mike please post the picture of that jumper. (mike is the owner)

So, any help would be helpful so Mike can get back home. I did tell him that there is alot of help in B'ham so he should be able to keep this on the road.
Thanks
Chad

 

BTW - Mike he is the atuo to 5 speed thread for down the road, much down the road.
https://www.rx7club.com/showthread.p...to+manual+swap

 

O'ya and I forgot to say no mods what so ever. Fully stock with all equipment in place.
Thanks

 

Last time I had that problem, the car was too low on gas to run properly.

 

Don't know how long it sat, but stale gas, but I would tend to look at the exhaust. How does the exhaust feel at the muffler tips, eg strong?
Y
ears ago I purchased a 350 Chevy wagon with the same symptons, and the owner thought it was the trans. It would start right up, put it in gear an it would hold an idle, but as soon as you gave it gas it was a no go. Got the car home and it turned out to be the exhaust pipe which was a 2 layer pipe, but the inner part collapsed. Replaced the pipe and fine.

 

Yes, hopefully he will drop the pipe today and run with it hanging just to see if that is the problem.

The gas tank is on 1/2 so 8 gallons of gas......


Thanks and keep them coming. I will post the fix if we figure it out.

 

Hi Guys...This is Mike, the owner of the 91 Vert...Chad, here's the pic of the jumpered fuel pump plug...btw, THANKS so much for your help with this...maybe I will get home eventually after all! Thanks everyone for your help!

 

I'm out to attempt to drop the pipe...I'll post after...

 

I had a bad TPS that caused my car to 'fall on its face'. Pull it and test its resistance range. My bad MAF was RPM dependent. Ran great in the areas that the AFM moved freely. Ran like garbage at RPMs that it 'hung up'.

Look for vacuum leaks.

You did change the fuel filter, right.

How are the plugs, wires, coils, air filters, 02 sensor, vacuum lines, intake hoses, and that sensor in the left corner of the above picture???

And, she'll limp out on you if there is ANY OMP issue. Run 1/2 dose of premix until you can verify MOP working condition.

 

The TPS I can test with my tester. The AFM was swapped out and it did not change anything.
The fuel filter was changed as well as the plugs. Air filter and coils are good.
The pressure sensors contacts were cleaned but not grounded with an extra ground as I read not to add an extra ground to S5 Pressure sensors.

The car has 92k on it. This should be an easy fix and probally related due to it sat awhile.
Keep posting your thoughts please.

 

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/troubleshooting-your-car-ecu-340578/

 

How many volts are you pulling with the fuel pump. Sometime's the wiring is the problem, not the pump itself.

 

Okay, I dropped the cats...no change. Also ran a can of Sea Foam in the gas & 1/2 can in the oil. Nothing. Still have to run the starter ground...will also be testing the fuel pressure and the TPS (tomorrow)...what else...haven't checked the fuel pump voltage yet...it's on the list. Thanks for all the input guys...keep 'em coming!

 

Ok, we checked the timing and it was set between both marks, so I set it dead on the mark. It ran a bit better but still the same problem.
So now that the car was warmed up I tested plugged in the RB TPS light tool and both lights were on with the motor off and key on. So I turned the TP screw till one light went off. Drove the car again and ran alot better and was able to hit 40mph but then fell on its face again. And that leaves us up to now.

Gonna try to get a fuel pressure tester tommorow and test the voltage at the fuel pump as well.
Maybe he will be able to drive home this weekend since he has been here now 3 weeks.


Keep the ideas coming

 

I can't believe no-one has mentioned the OMP yet... The ECU could be fried Chad, due to the Electronic OMP unit being bad... That send the car into limp mode, which doesn't usually result in stalling but will really limit the functionality of the car..

Search under limp mode, or bad OMP.

BTW I have a s5 OMP but no spare S5 ecu's...

 

Trevor, I have that spare S5 TII ecu I can use to see if the OMP is working.
Maybe Saturday you can run over and look over it as well? An extra set of eyes would do some good incase i am over looking something.


Mike, Do a search under limp mode, or bad OMP and see what you can find.
Also get that pipe back on if you can. Man those fumes! Ha ha

 

Be careful with the spare s5 ecu, the OMP will BLOW IT!! if it is bad it will fry the new one as well...

 

BTW: Put a code reader on it.. It will give a good idea if it is the OMP or not.

 

Yeah Chad, the fumes were outta' hand...but I got the exhaust hooked back up and grounded the starter. No change still...as of tonight, I haven't found a fuel pressure gage...hopefully tomorrow, or if you guys can scare one up...I'm off to make sure the butterflies are all clean, lubed & working properly...then on to the OMP & ECU I guess...then what... the injectors...God, I need to get home - lol!! Thanks again...!

 

Ok, update.

Mike sprayed the linkage outside and inside with carb cleaner yesterday. He could not get it to start again and flooded it.

I got there today and pulled the plugs. cleaned them, checked compression (65psi all 3 faces on the front // 35 psi all 3 faces on the rear). Knowing the car had been flooded I was not too worried about those numbers. I put in some MMO and put the plugs back in the correct way (splugs were 3 of the 9's and 1 7) and hooked up the plug wires the correct way as well. Turned the key and it still would not fire. Tried two more times, still no luck.

I looked over the intake, remembering he took it off the day before and found that it was not on all the way creating a major leak. So I pulled the plugs again and cleaned them. Checked compression again and the rear one came up to 75 on all 3 faces. Installed the plugs again and well, it still would not fire. So I smashed the windsheild and started to kick every body panel I could find!!!! No, I am kidding. I wanted to though!
So here is the deal. We have spark (checked), fuel (checked) and good compression but the stupid thing still will not start, so he is what I think is wrong.

I think the first day when I checked and changed the timing the plugs were swapped around and the wires were wrong as well. And now that the plugs are the correct ones in the right holes and the wires int he righ place that the timing is off again not allowing it to fire up. Does this sound correct?

On a S5 is pulling the EGI fuse the correct way to disable the Fuel pump?

Also can anyone tell me why the fuel connector (in pic above several post) has a jumper wire in it? I mean when it was running it ran the same plugged in or disconnected.

Please someone figure out this problem so Mike can go home!!!!!

 

Hey Chad- Jake here, I bought that 82 GSL from you last fall.

Seems to me that if there's spark, compression, and fuel, the only thing left to do should be time it out and make it run (famous last words...). I'd think that if it was set up some funky way and you got the timing set correctly/close for that, when you go to change the wires up you'd still have trouble with getting it to do what it's supposed to.

If it was carbed, I'd be looking for a problem with the accelerator pump or maybe a clogged jet in the secondaries- I would assume that there's gotta be some kind of analogue to that kind of trouble in the fuel injection world. Reasoning being that it gets going OK, then just dies.

Don't the S5 13b's have the "deflood" thing where you can push the gas all the way in while you crank and that cuts the fuel pump?

And if I'm clouding the issue with inexperience and conjecture, everybody just ignore me- just trying to help a local guy.

 

Jake,

Yes, I do thnk it is timing. I know how to align the timing marks on the pulleys but the CAS I am not sure of. I guess I can pull it out after I align the pully marks and the CAS will have marks on the bottom of it. Then insert it back in. Not too sure with the cas as I never had to completly time a CAS car and you can't look at the rotor button to see if it is pointing the right direction.

Other than that, that freaking jumper wire in the fuel pump plug buy the passenger side fender has me wondering why!

BTW - hit me up on a PM and let me know how the GSL is coming along.