gormant1

So its been about a year, but I am finally ready to get back to work on my 91 Formula. I decided it was best to work on one project at a time so I spent the last year finishing the restoration of my 70 Nova. Now its time to get my Firebird back on the road.

So the problem I was having goes like this: its very hard to get started, sometimes it actually kills the battery before the engine finally starts. When it finally cranks up, it skips something awful. And after about 30 minutes it shuts off and wont crank again until the car cools down. While its running it has about 45 lbs of fuel pressure and when it shuts off it still has fuel pressure.

So over the weekend I ran some tests. Replaced all 8 spark plugs. Tested all 8 injector harnesses with a noid light. They noid light lit up for each cylinder, so I am getting a pulse. Then I checked each of the injector ohms. They were as follows: 1-8 2-15 3-12 4-9 5-9 6-3 7-15 8-18. Clearly there is a problem on #6 with just 3 ohms. These are factory replacement injectors that are about 10 years old (for the past 6 years the car has sat up with very little running time on the engine) but only have about 15000 miles on them. So I ordered some Bosch 3 injectors from southbay and also bought a new distributor. I plan to get these items installed over the next couple of weekends.

My question is this: what is the normal number of ohms for the factory injectors and what kind of variance should you see among the 8 injectors? Does anybody have any thoughts on the ohms and the amount of variance that I found on my injectors?

Bob88GTA

iTrader: (2)

10 Ohms Minimum. At that point, start looking for new ones. Now that reading could be cold or hot. I would say cold. Things start getting exciting when warm, as in shorts and other things.

Injector Resistance Table 2_21_01.PDF

gormant1

The engine was cold when I checked all of the ohms.

Bob88GTA

iTrader: (2)

The reading on the chart that I was questioning. And yours, with the minimum run time on them, may be all clogged up and the coils can short out when hot.

gormant1

I wasn't aware that injectors had coils. That's interesting. I'm kind of doubting that my new injectors will arrive before the weekend so I will probably have to wait until next weekend to find out if I have found the silver bullet. Can't freaking wait....

Bob88GTA

iTrader: (2)

You'll love them. Just be aware that they are a tad noisy, a known fact with the Bosch III's.

Did you check your Fuel Pressure Regulator, buy an adjustable?? Might want to consider that while it's all apart for the injector install. JMO

gormant1

I have heard that they are noisy, but that's what the flowmaster exhaust is for, right?

I have had an adjustable regulator on it for about 10 years now. I set it at 48 psi. However, I never really noticed a difference no matter where I set it. I will be putting new O-rings on fuel rail though. I might even pull the intake to clean it all up if there is carbon build-up in the egr ports. I was getting an EGR code for a long time. I replaced the valve a couple of times, but the light always came back on. I'd like to get to the bottom of that as well. Any thoughts?

Bob88GTA

iTrader: (2)

Yeah, Flowmasters and Tunes! Good idea on the EGR/Intake clean-up;especially if you have the normal coolant leak at the seal.

On the EGR Code...is your EGR Solenoid in working order??

gormant1

Isn't the EGR solenoid located at the back of the intake, near the distributor? I don't know a lot about the EGR solenoid. I think I remember seeing it the last time I put new injectors in. How can I test it to see if it's functioning properly?

And what seal are you referring to with a coolant leak?

Bob88GTA

iTrader: (2)

The Intake Manifold Seal....known to leak



EGR Solenoid...It mounts with the Coil

Bob88GTA

iTrader: (2)

You can test it by taking it out and applying a 9v battery to the terminals while blowing through the ports, then reverse the voltage and blow through the other. The port on the rear of solenoid is the VENT, usually with a small piece of foam around it's port

gormant1

Ah yes, the intake. Being 24 years old and with 230,000 miles on it, I'm sure it's just about ready to blow.

Being the moron that I am when it comes to electricity, could you explain to me what you mean by "reverse the voltage". I would really appreciate it.

Also, do you happen to know if those solenoids are still available to purchase? Or is that a junk yard item only at this point?

Bob88GTA

iTrader: (2)

Just switch the leads to the other pin, it's a 3 pin connector

See this Thread, it may help out

https://www.thirdgen.org/forums/tech...oid+94+Deville

gormant1

Thanks. I think all of that makes sense to me. I guess I will find out when it put it to practice. Either way, I will let you know when the parts get here. Thanks again.

gormant1

So after a few weeks of setbacks because of weather and work, I finally got everything put back together yesterday afternoon. But now I have more troubles. First let me recap, I installed new injectors, fuel rail O-rings, valve cover gaskets, alternator, wired in a new Idle Air Control plug, new distributor, plugs and wires, and swapped out the EGR solenoid with one from a parts engine.

After getting it all put back together, I turned the key on to the prime the fuel system and got nothing from the fuel pump. It never made a sound and the fuel pressure gauge didn't budge. Then I realized that I had vice grips blocking off the inlet fuel line so that it wouldn't drip while I was working on it. So I took the vice grips off and turned the key again, only to get the same result....nothing. Before I started this project I didn't have any fuel pressure issues. While we were taking the alternator off, my brother forgot to disconnect the battery and arced off the hot lead. But I wouldn't think that that would be enough to take out a fuel pump. So I'm stumped.

So I guess my question is, how can I go about diagnosing my fuel pump issues? I know there is a fuel pump relay somewhere that I need to check. Are there any fuses related to the fuel pump? I would really like to be certain that the fuel pump is bad before I go through the trouble of dropping the tank to replace it. Any suggestions are greatly appreciated.