Detonation/Backfire Problem

[rmoulderoh]

I upgraded my 87 GN as follows:

- Walbro fuel pump with hot wire
- Adjustable fuel regulator (set at 40 PSI idle)
- Green stripe TOMCO injectors
- Lt1 3 " MAF
- MAF Translator
- Big Mouth cold air induction

It ran pretty well for a few weeks and then started backfiring/popping when I would go WOT. I changed the plugs out using E-3 plugs recommended by Kirban. It's backfiring/popping even worse now.

I've attached the TurboLink data from a run I made today. It was backfiring so badly, I really couldn't get into that hard.

Help?

[Royal-T]

What chip are you running? is it compatible with the translator/injectors?
Is FP static with vacuum line off or is that with the line on? What is you BL at? Any vacuum leaks? exhaust leaks? i have no experience with E3 plugs [except for my lawnmower] How much boost are you running? what octane?

[chrisgarrett]

A bad coilpack can cause backfiring.

[Keller]

Originally Posted by rmoulderoh

- Green stripe TOMCO injectors

What are they rated at? 30 Lb/hr? 42.5 Lb/hr?

Do you have a matching chip?

Chances are this is an issue with the ignition or the trigger wheel on the balancer being loose. Maybe even the balancer itself.

[rmoulderoh]

Thanks to all for the replies.

Answers to your questions:

- Stock chip
- 30 # injectors
- No vacuum /exhaust leaks
- FP @ 40 vacuum off
- New coil pack 3 years ago

Need to check BL.

I'm gonna go back to AC R44TS plugs and put some new wires on also.

[PaCemkr86]

subscribed

[rmoulderoh]

Update: I went for the easy fix and just put on new spark plug wires. The problem is gone! I suspect that during the replacement of the injectors, fuel regulator and spark plugs that the old wires got messed up. Anyway, just goes to show that looking at the simple stuff first is the best approach.

[Keller]

Originally Posted by rmoulderoh

Anyway, just goes to show that looking at the simple stuff first is the best approach.

Amen to that!

So the E3 plugs are still being used?

[Royal-T]

let us know how you like those E3 plugs and what kinda boost you run... good to hear it was just bad wires.

[PaCemkr86]

which wires did you go with???

ive had really good results with these
http://www.rjcracing.com/RJC_Buick_P...lug_wires.html