96 Tahoe dies while driving and won't start

[Nightflyer]

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..

 

[bigfootchiro]

Hi Matthias! Welcome to the forum! One of my good friends growing up was a transfer student from Germany named Matthias.

Keep in mind, I'm no expert when it comes to this, but I'll start by shedding some light for you, then hopefully more knowledgeable people will chime in.

How was the truck driving before all of this happened? Was it stumbling, misfiring, or lugging at all?

When you turn the key to the ON position, does the SECURITY light stay on, or does it go off?

Have you ever changed the original spider injection unit under the upper intake plenum? You can do a fuel leak-down test very easily with your fuel pressure gauge. Hook the gauge up to the schrader valve, turn the key to the ON position (do not start), and check your pressure. You said it was 61 PSI before. Turn the key OFF and see if the pressure drops. If it drops significantly over 5 minutes your fuel pressure regulator is probably bad.

I know you said you have good spark, but have you checked your ignition coil? Usually when people say something like, "someone cut the ignition," it's usually electrical related. Another piece could be the ignition switch itself has gone bad.

 

[Nightflyer]

Hi Nathan,

Thank you for your reply..

Before this happend, the chevy runs very well...okay, sometimes rough idle (when it was very warm) and a little bit stumbling. but when i remember, the car ws often hard to start when the engine was hot....

I don't have any security light and it's the original spider injector inside (200tm).

Okay.....i've done the fuel pressure test. It's holding the pressure for about 5 minutes...goes a little bit down do 60 or 59psi.

I've changed the ignition coil...it's a new one.

best regards

Matthias

 

[bigfootchiro]

Doesn't sound like the spider is bad. When was the last time the fuel filter was changed? With that much pressure, I would not think it would be clogged, but if it has been a long time since it was changed, might as well change that for maintenance.

What brand of ignition coil, cap, and rotor did you use, and how long ago did you change it?

There's the potential of a bad ground wire, as well. I'm mind vomiting every possibility that I can think of that would cause a no-start condition. Hopefully someone else will chime in, as well.

 

[Nightflyer]

Okay,

I've doublechecked the spark plugs after some cranking the engine.....6 of them are dry...no fuel....

The fuel filter is new...changed it last month....

Ignition coil, cap and rotor are from delco.

Well, i can improve a ground wire an test it..

 

[Nightflyer]

Okay....

All ground wires are in good condition.

I think it's better to install a new spider assembly....

What's the difference between cpfi and mpfi? is it easy to convert it?

I've seen, there are different diameter available...5mm and 6,5mm. My 8digit at the vin-code is an "R"...so i think i've 5mm injectors diameter, right..???

Best regards from Gerrmany

Matthias

 

[bigfootchiro]

The spider may or may not be the cause, but if you're wanting to do it anyway, go with MPFI. The difference is central port vs. multiport fuel injection. The MPFI is with the upgraded injector unit that is controlled at each injector. I did the upgrade and the truck runs much smoother now. IDK what your prices are in Germany, but the cheapest I found was on Amazon. Even found some on eBay that were cheaper.

 

[Nightflyer]

Hi Nathan,

I do not know what else it could be..

I've spark, Battery is in good condition, the car cranks, the fuel pressure is ok...everything i fine....but no fuel at the spark plugs and no trouble codes. The fuel reaches the schrader valve with the right pressure...

In germany is the spider-injector very expensive. The car is rare here...it's about 500-600€. Rockauto or ebay (with new FPR) ~240€ and one week....)

I just need to know wich diameter in need....??

 

[bigfootchiro]

The part number you are looking for is ACDelco 19210687. I've never seen a diameter size for the injectors, but that is the part number you would need. Can you post a link to the site where it asks for the diameter?

 

[Nightflyer]

Here is the link....

http://www.rockauto.com/de/catalog/...5.7l+v8,1061356,fuel+&+air,fuel+injector,6224

In the ite description is 5mm and 6.5mm listed