Edited to clear things up

Recently bought an 88 camaro and dropped in a 350, today was suppose to be the day i fired it up for the first time but things didn't go my way. Here's the details..

88 camaro, 305 tbi car, auto
5.7 tbi from a 92/93 buick roadmaster(ran fine in the Buick, same distributor)
fuel pump will prime, car will crank, but will not start
I do have power to injectors but they are not pulsing
I do have power to the coil and to the icm(pink wire)
I've checked fuses under dash and in line fuses by battery, all are good. Any fuses I've missed?

I'm out of ideas and very frustrated.

 

Check out response #5 on this thread to see if your coil and pick-up coil are okay.

https://www.thirdgen.org/forums/elec...ol-module.html

Also check your ohms on your injectors - the coils in them may be shot. #5 on this thread.

https://www.thirdgen.org/forums/tech...ease-help.html

Good luck.

 

If you are using the 88 harness, check your ECM fuse, it powers the ECM, the Passkey module and the EST. Wiring diagram on Austinthirdgen.org. HTH!

 

Thanks for the reply. I know all of this is good, or at least was a very short time ago. The engine, with same distributor and injectors, ran great in the buick.

I checked the ecm fuse under dash, is there another? I'm checking austinthirdgen.org now...thanks

 

Edit: never mind this post, I've been confused about how the system works. From what I've read the 4 wire connector at the distributor sends signal back to the ecm. I thought it was the other way around.

 

Ok so now I'm wondering if a bad oil pressure switch will prevent the injectors from supplying gas to crank the engine? I discovered that my oil pressure switch was broke. Does the ecu need to see oil pressure before the injectors will pulse?

 

Oil pressure switch controls oil pressure gauge and auxiliary contact runs fuel pump if fuel pump relay fails. That is, if oil pressure present, contact closes and supplies voltage to the fuel pump. ECM will pulse injectors if, VATS is ok and distributor sends DRPs to ECM (ignition control module). Go to ChevyThunder.com, there is a comprehensive troubleshooting guide for the distributor and EST circuits. HTH!

 

change distributor. That happened to me. You will have power to injectors. That current stays steady, its the ground that pulses.

 

I bought a multimeter and followed the tests from the link. I got questionable readings on the coil and pick up. I'll probably try to replace the pick up and see what happens. Hard to trust my multimeter skills since I've never used one before a couple hours ago.

 

my problem was the most challenging of all, so far. You will find you colors change when they go thru the firewall. There are 3 wires for the grounding signal. I unhooked the ecm and the wires at the distributer and tested for continuity. It was good. Since I already had a new ecm, I knew it was the distributer. About 70 bucks complete at Oreileys with lifetime. My car started right up.

 

Wouldn't it be possible that it was just the module in the distributor?

My problem with replacing parts in the distributor is that this engine/distributor worked fine in the other car. I feel like I must have left something unhooked or my ecm is to blame.

 

You have no power to the ignition module in the distributor? Of course it won't start.

If the module has no power, the engine won't run. There will be no injector pulse. There will be no spark.

Do you have power to the ignition coil?

 

Sorry for my bad info in previous posts

 

No spark, no injector pulse is a sign of a defective pickup coil in the distributor, or a defective ignition module.

A wiring-harness break could also cause the problem, and, I suppose, a defective ECM.

"I" would be doing some distributor diagnosis. You'll want a spark-tester and jumper wire. Any chance you have a 450-watt soldering iron? A test-light?

This write-up is not specifically intended for TBI distributors or computer-control ignition systems, but the basic procedures are well-covered.
http://www.chevelles.com/techref/ftecref5.html

 

Turns out the ignition control module was bad. After inspecting it closer, there was a hairline crack going straight across the top of it. The car will start and run now but for some reason only one injector is working. I used a test light to check for a ground pulse but, instead of pulsing, my test light dimly illuminated constantly with the engine running. With engine off the test light shows the wire isn't grounded at all.

Thanks for the help guys

 

Excellent. You're most of the way home, now.

Power is supplied when the key is "on" or in "crank". When the ECM gets the signal that the crankshaft is rotating (via the distributor pickup coil and ignition module) it pulses the ground for the injectors. The injectors spray when they're grounded by the ECM.

Getting a dim test light with the engine running is probably telling you that the ground is pulsing--it's not grounded all the time, and it's not failing to ground. You're getting a dim light because the injector duty cycle is more than 0% and less than 100%.

First Guess: The injector solenoid is stuck. Gummed-up with stale fuel.

I had one just like that. Swapped throttle bodies with one from a salvage yard. Engine ran on four cylinders because one injector wouldn't spray. Switched wire harness between the two injectors. Same injector fired, same injector didn't. That told me that the wiring and the ECM were fine--which made sense because the original injectors fired just fine.

As I'm thinking about how to fix this, "poof" the dead injector starts firing. Took about five minutes of engine running to free it up. I've had zero problems with that injector ever since--several years now.

Run the engine, see what happens. Wouldn't hurt to drop a bottle of injector cleaner in the gas tank, but that may or may not actually help.






For the record, the engine in my K1500 is a crate-engine replacement for the '92 Caprice 5.7L, similar to yours. The power isn't much better than the original, but roller lifters can't hurt durability. The short-block is VERY similar to the 330-hp 350HO crate engine, except the cam is very mild, and the block has two-bolt mains. The 350HO has way better cylinder heads. That and the camshaft make all the difference.

 

Awesome. I'll swap over the injector harness this evening and see what happens. If the same injector fires then I'll know what the problem is.

And yeah, this engine is rated at a whopping 180 hp. The good thing is it's a $300 engine that I heard run before purchasing so i can't really complain. I plan to run it just like it is for now and maybe over time collect the parts to rebuild it right.