1988 astro no fuel

[Painter]

I have a 1988 Astro van 6 cyl, Throttle Body Injection, and I'm not getting any fuel out of the (2) Fuel Injectors. I replacet the Fuel Pump and have fuel at the Injectors. There is 12 volts at the Injector wire. I checked for any codes and it only flashes code 12. It will start if I prime the Throttle Body, and stops as soon as the fuel is burned.

[wadee]

Have you checked to see what pressure you are getting? I have heard that they need a specific presssure for the injector to oporate (60psi at start up). The fuel pressure regulator could be faulty!

[Painter]

I replaced the The fuel pressure regulator and Im still not getting any fuel out of the injectors.

[CD Smalley]

TBI engine would only need 9-13psi.

There is an oil pressure sensor switch located somwhere. It it fails and the ECM thinks you are not generating enough oil pressure it will not allow the injectors to fire.....

[Painter]

When I crank it over the oil pressure light goes out. Could it be the Throttle Position Sensor?

[CD Smalley]

The sensor for the light and this one are seperate.


Are you getting spark? Hook a timing light up to one of the wires and crank it. The timing light will flash if you are.

If not the ignition module, under the distributor cap, may have gone south.

[Painter]

I do have spark, and the engine starts if I put fuel in the TB, but as soon as the fuel is burned it stops. Looking at the wireing diagram for the oil pressure sensor switch it sends power the the fuel pump after the fuel pump relay kicks out once the engine is started. It seems the engine should start, but if the oil pressure sensor switch was bad the engine would stop. How do I check the oil pressure sensor switch?

[Painter]

I checked the Throttle Position Sensor, and the oil pressure sensor switch, all I could find is one sensor. The book shows two in the same loacaion. still no fuel :-( it may be time for the van to go into the shop!

[CD Smalley]

How'd you check the oil pressure switch?

And what manual are you reading?

[Painter]

I'm using two diferant Chiltons Repair Manual for the Astro van one is for 1985 - 1990, and the other one is for 1985 - 1996.
the oil pressure switch is ether open or closed.

[CD Smalley]

Hmm.. I'm stumped. You've got spark and fuel pressure, just the injectors won't fire.... I think that oil pressure switch is bad. But without having my hands on the van....

[Painter]

Ya I'm stumped to. I found out that the book shows 2 switches: one is for a guage, and the other is for a dash light. I have the one with a dash light. Ya with gas, and fuel pressure it seems to be some sensor not telling the ECM to fire the Injectors. I found in the Repair Manual that if ECM reports a code 12 with no other faults it could be a bad ECM. I'm also thinking that the Injectors could be bad but it takes a GM tool to check for the paulse measurement. The Repair Manual checks the oil switch if the light does not go out by ohm reading on the switch when there is oil presure. if it's open replace the switch. I'ts going into the shop, I will let you know what they find wrong with it.

[CD Smalley]

The ECM could be the problem I guess. I really doubt the injectors... The TBI injectors are nearly bullet proof. They just rarely if ever fail. My 92 Astro had over 200k miles on the OEM injectors. Let us know what the shop says 'cause I'm stumped.

[dimotorsports]

CD, PAINTER!

Check this out!
My 87 does it too!
I am about to burn it to the ground!

Background: 87 Safari, 4.3 V6, Auto, 2wd, 165k mi.

I have replaced nearly everything under the sun..
Here's list of new items right off the top of my head:

Fuel pump, relay, fuel filter, injectors, regulator..
Dist. cap, rotor, plugs, wires, coil, ign. pickup, finally the distributor.

PCM, TPS, EGR, IAC, O2, EGR sel., All vaccum lines, PCV, Air filter, cleaned the TBI body...

I am looking into a bad engine ground, possible bad PROM and CALPAK now, but I am grasping for straws...

Here's an exaple of what it does...
Short trips with long (couple hours) lay overs.. Van is fine.
Long trips with short lay overs... your stuck.

Just a while ago...
I went out, cranked the van first try, drove it around the block several times while cold. Came back, parked it in the drive and let idle for about 30 min., when I came out to check it, it was not running and would no longer start..

When this happens... there is no fuel sprayed by the injectors.

I am tired of chasing this problem and being towed home..
If anyone has some insight... please help.

[reallytired]

This sounds about like the problem I'm also currently working on. I haven't done as many checks on the different components as you have discussed here, but almost everything sounds the same.

I have a little newer Astro, 93, with 12 showing on the diag codes and the van is not starting. It started out not starting on occasion- not affected by cold or hot weather. Changed out the cap & rotor, because they definitely needed changed. Drove it around the block, before it stalled again on the way back at a stop sign. Since then it only seems to run 1-2 minutes before it dies - if it will start. Most of the time it does not start. Fuel filter was changed about a year ago, suppose to last quite a while from what I understand. I just changed out the fuel pump, because one of my friends said that it is what it is sounding like & I had similiar symptoms back when I changed out a fuel pump on a Caravan - fixed it then. Cost of pump vs. pressure gauge was same also, but definitely not the work involved. I have watched the injectors shooting fuel into the throttle body when it starts, but when it does not start, no matter how many times it does turns over the injector does not let out any fuel.

So do I need to check the oil pressure sensor, throttle position sensor,
or ecm? If there is anything else let me know.

I have not checked the fire, but I will definitely double check that with a timing light