96 Tahoe dies while driving and won't start

[wolfeman2120]

The key here is to make sure you have fuel and spark.

based on what information was provided, here's what I would do. Check to make sure you have spark at the end of each plug wire. Use a test light for this and have someone crank the engine. If you have spark at all 8 cylinders then its likely a fuel supply issue.

You checked the fuel pressure at the schradar valve so you know the pump isn't suspect yet. The likely culprit is either the injectors or the fuel pressure regulator. Since its one unit, your better off replacing the whole thing. Also replace your fuel filter and flush the fuel lines when you do it.

Since the vehicle is over 20 years old with the CPI I would blame that as they are known for clogging with carbon. The injectors themselves could be fine, but the inside is likely full of crap preventing it from working right. And if that regulator is bad then it won't open the injectors.

Its also possible that injectors 1 and 4 are not closing correctly and leaking fuel into the cylinder when it is pressurized. Overnight you might see that fuel pressure drops.

 

[muncie21]

I had a Tahoe that would crank and not fire, however come back an hour or day later and it would start no problem. It did this intermittently, with no discernibly pattern. I tested/replaced most of the things that have been suggested in this thread.

After exhausting all other possibilities, I was left with only the PCM. I purchased a used PCM however the truck didn't give me any problems from that point until I sold it about 4-6 months later.

 

[Beechwood]

I had the same problem on my '99. After changing $500 worth of sensors and ignition components, I brought it to my mechanic.

It was the wire harness touching the exhaust manifold behind the motor I couldn't see. One wire was grounded out.

Was a $1 fix....

 

[muncie21]

I had the same problem on my '99. After changing $500 worth of sensors and ignition components, I brought it to my mechanic.

It was the wire harness touching the exhaust manifold behind the motor I couldn't see. One wire was grounded out.

Was a $1 fix....

That's a very great (observant) mechanic. Keep him on your Christmas card list!!

 

[bayviewnick]

Hello Matthias,
I don't know where you are in your plight and have not yet read all of your responses. To save time, I'll get to the point. I had a 1999 Tahoe with a 5.7 (350) TBI that used to stall out and not start. Wait anywhere from a few hours to two weeks and it would restart only to do the same a few days later.
Four garages changed: spark plugs (twice), coil, fuel pump, wires and cap. Two suggested the fuel spider was bad. As it turns out my problem was the crank sensor. The crank sensor doesn't need replacing to trouble shoot, it can be ohmed out. I hope this helps you.

 

[nathanhanover]

Hey Guys,

I'm Matthias from Bamberg, Germany. I've an 96 Tahoe (350 Vortec TBI) and a real big problem:

My car died three weeks ago while i'm driving (it was like, someone cut off the ignition) and won't start again. Nobdy in Bavaria and Germany knows why.....

- the battery is in a very good condition
- the car cranks very well but won't start
- the chevy has very good sparks
- the fuel pump is running and new
- fuel pressure at schrader-valve (is that the name?) is about 61psi and 63 while cranking
- changed the distributor cap, rotor, plugs and wires
- changed the ICM
- changed the CKP-sensor
- it misfires whit starting fluid (one time)
- the plugs are sometimes wet and you cann (sometimes) smell gas
- the timing chain is okay (tested with turning the crankshaft and look at the distributor..the rotor moves

sometimes it seems like, that the chevy would like to start. it sounds like, that there is no pulse to the injectors.

btw: there are no codes stored in the PCM and all cables ok.

Please: could someone help me? what can i test and look for?

Best regards from Bavaria/Germany

Matthias

p.s.: soorry fpr my bad english..

 

[nathanhanover]

had the exact same thing with my 1996 2 door 2wd, replaced the Distributor cause it had 200 k, still wouldn't fire. Kept checking found that the Brand new rotor cap had a short. Replaced it and wallah!

 

[JonnyTahoe]

had the exact same thing with my 1996 2 door 2wd, replaced the Distributor cause it had 200 k, still wouldn't fire. Kept checking found that the Brand new rotor cap had a short. Replaced it and wallah!

As many of us have found out working on these Distributors in the limited space you have is a real pain. The stories people have shared are interesting I never would have suspected a Crank Sensor or Knock Sensor and certainly not a wire grounding out on a Exhaust Manifold. These are very dependable trucks and when they stop running we all go back to the Basics to find the cause and start "Throwing Parts" at them. Sometimes we get lucky sometimes we don't.

 

[JonnyTahoe]

I had the same problem on my '99. After changing $500 worth of sensors and ignition components, I brought it to my mechanic.

It was the wire harness touching the exhaust manifold behind the motor I couldn't see. One wire was grounded out.

Was a $1 fix....

 

[JonnyTahoe]

And I was upset about a hundred.