TBI conversion question (1 Viewer)

[Webster]

Converted my landcruiser to GM TBI. Was running fine when parked Friday. Won't start yesterday. Got fuel pressure but nothing squirting out of the injectors. Can anyone point me towards the most obvious or likely causes of the injectors not opening?

Thanks!

Chris

 

[woody]

did you disconnect power and reset the computer?

 

[Webster]

I pull the fuses long enough to look at them to see if blown. How do you reset the computer. Disconnect power for 30 minutes?

 

[woody]

I don't believe it even takes that long...also, you do have your ALDL available to check for codes, right? Anything come out of that?

 

[Webster]

Since my check engine light wasn't flashing I didn't figure there would be any codes to find. I will definately check this evening. Thanks

 

[Gumby]

Most obvious place to start would be the fuel pump. Does it run for a couple of second with the key on engine off? Does it run when cranking? Is there fuel pressure at the TBI unit? If no, then you need to jump the test terminal at the relay to determine if the ECM is the cause, or the relay or the pump.

(just re-read and noticed you said you have fuel pressure. You could check for full pressure, but if it pumps chances are reasonable that it's OK)

Second place I'd go is power to the injectors. Got 12V at the red terminal? If not, check the injector fuse.
Power to the injectors OK, then check the wires and connections from the distributer. Try to start it on starting fluid. IF it starts, then the distributer is getting power and the pick up coil and module are working. There could still be problems there, but the odds are a lot slimmer.
Then I'd back probe the ECM to check for power at the ign and constant wires. Then I'd check the ECM grounds.
If the above doesn't help, then I'd get back on the forum and ask some more.
Resetting the ECM takes a few seconds with no power.

 

[woody]

With the issues I just had on my TBI setup, the check engine light didn't come on, but the WinALDL noted a code, first the O2 and then the MAP.

 

[Webster]

Well of course I disconnected power before checking for codes. I did try starting first though. Anyways no error codes stored.

Wouldn't start or fire with starter fluid. Didn't get any farther.

Obviously something goofy with the idnition module/coil, or its connections.

Any other ideas?

Thanks!

Chris

 

[Gumby]

Check for spark at the plugs. If no spark, check for 12V to the coil. If that's good don't forget to check is that the distributer is moving. Cranking with the dizzy cap off will tell you that. THen we need to know what type of ignition you're running. csb w/ HEI, 2F w/ HEI or 2F w/ modified Toy dizzy.

Assuming you're running HEI, you can ohm out the coil and the pick up coil, then test the module. There are a couple of web pages that have the procedure. You'll need a test light and a spark tester.