jmat2407

iTrader: (-1)

Ok so trying to get this damn car on the road and out of the garage.

When I turn the key the engine will spin/crank but it wont ever start/run. However, if I spray ether/starting fluid into the tb it will fire up and be ok. I can let it sit there 2 min, or 20 min, but once I turn the car off and try to restart it the same thing happens again.

So far I have..

set the timing properly
replaced plugs, wires, ignition module, and ignition coil.

Previous owner had replaced cap/rotor less than 3 months before I bought it.

Also I ohm'd out the ignition pick-up coil to 900 ohms, service manual says 500-1500 is ok.

So what should I try now to fix this start up issue?

edit: btw its an 89 gta 5.7 TPI

JTNKTZ

iTrader: (10)

I'm not familiar with TPI but I'm going to try. When you turn your key to ON position, can you hear your fuel pump prime?

Theres a fuel pump relay on the firewall (Drivers Side, theres 2 relays not sure which). The gray wire goes to the fuel pump. When the ignition goes into the ON position it should prime for 2 secs so see if you get 12v there or if you here the fuel pump turn on. For some reason it's not priming fuel.

Also, the fuel pump is turned on by the OPSU (oil pressure sending unit). When there's oil pressure, the OPSU sends 12v to the fuel pump. If the OPSU can only measure high PSI of oil and not low, the initial crank from the starter won't build up enough PSI, that could be why it won't start on it's own as well.

I would try to put 12v to the fuel pump than try to start it and go from there.

jmat2407

iTrader: (-1)

thx but the fuel pump is already priming.

also if i start it with starting fluid and let it run for a while it is not showing a ses light or storing any codes.

pgmonster

my sister was having that same problem on her 92 firebird TBI i thought it was the fuel pump to and i put new one in and it solved the problem for a few weeks but then it started to do it every so often and then we replaced the injectors and it hasent had that problem for 2 1/2 months

pgmonster

ok so here is what i would do first check for fuel pressure then

1. Ohm the fuel injectors, replace any under 15.8 ohms.

2. Check spark at the spark plugs with a spark tester set to 30KV. If it won't fire bright blue, check at the coil. If still weak, verify power and grounds and replace the coil.

3. If good spark at the coil and weak at plugs, check the cap/rotor/wires/timing.

4. Check scan data for sensor inputs, fuel quality and injector spray patterns. Verify the grounds are good.
HOPE IT HELPS

Krik

iTrader: (4)

I had the same problem. Unhook 1 injector at a time and try to start the car. If it doesn't start, re hook that one up then unhook the next one all the way around. When is does start, the one thats unplugged is the bad/burnt one. Replace with GM parts, not cheap autozone ones.

Post results please.

jmat2407

iTrader: (-1)

well I've already replaced the coil earlier today so guess my next idea tomorrow will be to check the fuel pressure in the rail and ohm out the injectors

pgmonster

Sounds cool be sure to tell me how it turns out!!!

jmat2407

iTrader: (-1)

So a little extra info i wanted to add...

if the car sits for about an hour or more it will start on the 3rd or 4th click. but you can turn it off RIGHT AFTER it starts and it still wont start again on its own without starter fluid for another hour or so. So its like you get one time for it to fire up, then no matter if you run it for 1 min or an hour it will not start but up on its own. wtf could this be?

Krik

iTrader: (4)

Did you follow my advise?

jmat2407

iTrader: (-1)

not yet im testing the injectors right now as i type this, so far im reading..

1- 17 ohms
3- 6 ohms

2-9 ohms
4-14 ohms
6-14 ohms.

budget350

you answered your own question lol. Bad injectors.

jmat2407

iTrader: (-1)

yeah i realize the injectors are out of the correct ohm range, but could this alone be the cause of my issue or you guys think its something else too?

pgmonster

yes it can but if you want to be sure it will work go ahead and get an oil pressure sensor because that could also cause the same problem. hope you get it fixed!

Krik

iTrader: (4)

Unhook one at a time and try to start the car

The fuse won't blow because the load is spread across 4 injectors (1 fuse per 4 injectors).

jmat2407

iTrader: (-1)

I just wanted to update... I followed ur advice man and it did just what you said it would. I have three injectors reading less than 12 ohms, when I unhook each of them she'll fire up, plug them back in, nothing.

Will be ordering a new set of injectors in the morning, any recommendations?

Again I really appreciate the advise man now that I know whats wrong shouldn't be to much longer b4 I get her out on the road.

Krik

iTrader: (4)

Yeah, i do have some good advice. Buy genuine GM parts, don't cheap out. You have to take off your intake to change them so change out your EGR while its off. Protect your gaskets and you can reuse them, if they tear get new ones. DO NOT USE GASKET SEALER, it will look terrible and is not necessary.

This is a good time to clean all those parts too. Hard to do while everythings still attached.