1997 Chevy Suburban THE MISSING FIRE GUY.

Tiny
VAUSE
  • MEMBER
  • 1997 CHEVROLET SUBURBAN
  • V8
  • 2WD
  • AUTOMATIC
  • 97,000 MILES
HI I HAD REPLACE EVERY THING IN THIS TRUCK.I JUST BUT NEW FUEL FILTER WIRES PLUGS CAP EVERY THING. IT RUN GREAT FOR ABOUT TEN MIN AND THEN IT START.I DO NOT NO IF IT IS MISS FIREING OR IT IS RUNNIG OUT GAS. THE ONE THING I HAVE NOT BUT NO NEW IS A FUEL PUMP. TPS COMP MAP EVERY SENSOR HAS BEEN BUT ON NEW. IF YOU GET IN IT YOU THINK I, M CRAZY BECAUSE IT RUNS SO GOOD FOR A WHILE AND THEN IT DOES THAT.I PUT THE COMP ON IT AND EVERY THING IS FINE. PLEASE HELP.
Do you
have the same problem?
Yes
No
Wednesday, December 12th, 2007 AT 6:29 PM

10 Replies

Tiny
MHPAUTOS
  • EXPERT
Hi there,

I would hook up a fuel pressure gauge and watch the fuel pressure when it starts to falter, this will help eliminate or confirm a fuel issue.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Wednesday, December 12th, 2007 AT 10:45 PM
Tiny
VAUSE
  • MEMBER
[quote="mhpautos"]Hi there,

i check the fuel it look ok.I just dove it to something came up it siad missfire in all cly. So we took change the cap and rotor and plugs again. So it did it again. So we change the camshaft, crankshaft, ignition control, coil, but it still does it. Thier some thing we see that when it is cold out side it does but when it is warm it does not do it. On the comp when we check the iat it said the temp is 52 ds goes up too 98 and that it. So we do not no but it was very cold the day we check it outside was 15 ds maybe that why it read 52 to 95. Need your help we can fine what wrong.
Was this
answer
helpful?
Yes
No
Friday, December 14th, 2007 AT 2:16 PM
Tiny
VAUSE
  • MEMBER
Check the fuel it look ok.I just dove it to something came up it siad missfire in all cly. So we took change the cap and rotor and plugs again. So it did it again. So we change the camshaft, crankshaft, ignition control, coil, but it still does it. Thier some thing we see that when it is cold out side it does but when it is warm it does not do it. On the comp when we check the iat it said the temp is 52 ds goes up too 98 and that it. So we do not no but it was very cold the day we check it outside was 15 ds maybe that why it read 52 to 95. Need your help we can fine what wrong.
Was this
answer
helpful?
Yes
No
Friday, December 14th, 2007 AT 2:25 PM
Tiny
MHPAUTOS
  • EXPERT
This may be related to the cold air. If MAF & MAP sensors are being affected by the very cold air, it will up set the air/fuel ratio and give driveability problems. They are expensive items to just change over to see if it works or not. I would warm up the car first and see if the air intake is using full outside air, I had a problem with a customers Toyota many years ago, cold snap caused this type of problem, I redirected warmer under bonnet air into the air cleaner and solved the problem, The cost was a small drop in economy, but that was only for a short cold spell in what is normally a warm temperate zone.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Friday, December 14th, 2007 AT 2:48 PM
Tiny
VAUSE
  • MEMBER
SO YOU THINK IT WILL COST IT TO SAID MISS FIRE IN ALL CLY. SO IT IS NOT A FUEL PROM OR A ELE PROM.I SEE IF I CAN BUT MORE WARM AIR IN TO IT.I WILL PUT A OTHER PICES TO THE INTAKE. CAN YOU WRITE TO WHAT I SAID ABOUT THE MISS FIRE IN ALL CLY.
Was this
answer
helpful?
Yes
No
Friday, December 14th, 2007 AT 2:59 PM
Tiny
MHPAUTOS
  • EXPERT
To get a true picture of what is going on as far as the miss fire, is to know exactly what is happening in the ignition and exhaust. We can normally point you in the correct direction as to what may be wrong, but some times it's not that simple, especially if you are trying to diagnose something from a computer terminal. So what you will have to do is ramp up the diagnostics at bit. Codes are one thing to look at, but to see what is happening with the ignition is to have it run on an oscilloscope and exhaust gas analyzer, the scope will give you an exact picture as to what the ignition is doing, Voltages, durations, cross firings, coil problems and the gas analyzer will give an insight into the mixtures and emissions, these things you can only speculate on with out the gear. Often you can have a problem that is quite common and the fix is well known, but others are a bit more complex and some detailed diagnostics is required, I feel that you will benefit from a scope reading.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Friday, December 14th, 2007 AT 4:59 PM
Tiny
VAUSE
  • MEMBER
I did every thing to make warm the intake now it read fine. But it got real bad now it is getting worst now for me to go on the night some times I have to floor it for it to go. It said still miss fire in all cly. It is run very bad does not gone more that 50 mph now with miss fireing very bad. Plaese help. It still sound like i, m run out gas or somthing.
Was this
answer
helpful?
Yes
No
Tuesday, December 18th, 2007 AT 3:05 PM
Tiny
MHPAUTOS
  • EXPERT
Hi there,

Check fuel filter, and drain a little fuel out of old filter, is there water in it? Did you check fuel pressure with a gauge? Make sure any warm air intake is not restricting are flow, an oscilloscope reading may be required to check ignition system more carefully.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Tuesday, December 18th, 2007 AT 4:11 PM
Tiny
VAUSE
  • MEMBER
I have change the fuel filter i, m gone to change it to see if thier was something wrong with it.I, m gone to check the fuel press torr doing the day.I will let you no.I, m real happy for your help just want to said thank you.
Was this
answer
helpful?
Yes
No
Tuesday, December 18th, 2007 AT 4:30 PM
Tiny
VAUSE
  • MEMBER
HI I TOOK IT TO THE SHOP TODAY AND THEY SAID THAT THEY DO NOT NO WHAT WRONG WITH IT. FUEL PRESS READ GOOD EVERY THING WAS GOOD. THEY TOLD THAT MAYBE IS THE FUEL PUMP THAT ACTS UP SOMETIMES OR THE FUEL PRESS REG BECAUSE IT FIX IT SELF AFTER A WHILE WHEN IT MISS FIRE THAN IT RUN GOOD AND THAN IT GOES BACK RUNNING BAD. THEY HAD CHANGE THE FUEL PRESS REG IN THE DEALER LIKE 8 MONTHS AGO. PLEASE LET ME NO WHAT YOU THINK.
Was this
answer
helpful?
Yes
No
Wednesday, December 19th, 2007 AT 7:12 PM

Please login or register to post a reply.

Recommended Guides