injector problem or coil pack problem?

[Aurora40]

How was the fuel pressure? What did the #1 plug look like? You might also check the FPR's vacuum line to see if there's gas in it.

You can buy a spark tester for like $10, they sort of look like a spark plug but with a weird end.

I wouldn't think only one cylinder down would be as bad as the symptoms you are describing.

[Jim Nolan]

If it is the injectors they must be in very bad condition. When I pulled mine for the porting my secondaries were very corroded, but my ZR1 ran very good and never burped once.

[GOLDCYLON]

Originally Posted by Jim Nolan

If it is the injectors they must be in very bad condition. When I pulled mine for the porting my secondaries were very corroded, but my ZR1 ran very good and never burped once.

Mine were rusty as hell as well. Wont happen with RCs as they have a stainless steel insert.

[ZZZZZR1]

Injector #1 was bad...

Jim said from day 1 what it was and sure enough!

[GOLDCYLON]

Originally Posted by ZZZZZR1

Injector #1 was bad...

Jim said from day 1 what it was and sure enough!

Actually I did in post #2 but hey its up and running. But I would still my FUs complete set

[FU]

Originally Posted by GOLDCYLON

But I would still my FUs complete set

Thanks for the mention Daryll

Plus all the proceeds go to a great cause.And if you have a a 90-92 , your going to need them sooner or later .

[QB93Z]

Follow up on the problem:

The symptoms were: loss of power, rough, stumbling operation, stalling at idle, hard to start, and white smoke at the exhaust that smelled like gasoline.

Pulling spark plug wires showed no change in rough idle for #1 plug wire. All other plug wires made the idle worse.

Fuel leak down test: ignition key to on, fuel pressure steady at about 50 psi. Ignition key to off, fuel pressure immediately dropped to zero.

Pulled the Plenum. Turn the ignition key to on, observed fuel squirting from #1 primary injector.

We replaced the bad #1 injector with a used injector to get the car running again.

Jim

[Jagdpanzer]

Originally Posted by QB93Z

Follow up on the problem:

The symptoms were: loss of power, rough, stumbling operation, stalling at idle, hard to start, and white smoke at the exhaust that smelled like gasoline.

Pulling spark plug wires showed no change in rough idle for #1 plug wire. All other plug wires made the idle worse.

Fuel leak down test: ignition key to on, fuel pressure steady at about 50 psi. Ignition key to off, fuel pressure immediately dropped to zero.

Pulled the Plenum. Turn the ignition key to on, observed fuel squirting from #1 primary injector.

We replaced the bad #1 injector with a used injector to get the car running again.

Jim

Well done skipper, I hear by promote you to honorary Engineman

[HIZNHRZ]

Here's the link from Marc Haibecks website for isolating bad fuel injectors. All you need is a digital multimeter and the ability to follow the instructions. Bob and I used it a little over a year ago. It gives you the ability to determine if any others are on the way out.

http://www.zr1specialist.com/HAT%20W...in%20Place.pdf

[QB93Z]

Originally Posted by HIZNHRZ

Here's the link from Marc Haibecks website for isolating bad fuel injectors. All you need is a digital multimeter and the ability to follow the instructions. Bob and I used it a little over a year ago. It gives you the ability to determine if any others are on the way out.

http://www.zr1specialist.com/HAT%20W...in%20Place.pdf

Thanks for the link. The injector failure that occurred was mechanical (stuck open), so it did not have an electrical problem that we could have measured.

Jim