Seems an old prolbem is back to haunt me. After yanking the engine and rebuilding, I get it all put back together and plug everything in, only to find it doesnt start up, so I pull the plug out of the MAF and it starts up. Ive replaced the MAF, both relays, IAC, TPS before already, can I safely assume that the ECM is the source of my problem? Is there any way to tell for sure? Another question also, I time the engine and by the time I tighten down the dizzy, the timeing is off again, confuses me a bit. Thanks for any help!

 

Anyone? Im planning on getting my Y-pipe made next week and getting her back on the road, would like to exorcise any demons this weekend if I can.

 

I have a similar problem....
After months of tuning my electronic carb using an air/fuel ratio guage ... last weekend I installed Bosch platinum 4 plugs and 160deg stat... now the timing is erratic and advanced to 43deg from 27deg without moving the distributor, 3000rpm and it goes to 55deg.

also....can someone tell me what exactly does the ignition module do....now when I unplug the timing lead from the distributor the engine stalls and won't fire until it's plugged back in!!!


any thoughts?

Ported World 305 heads
Herbert Cam 217 / 223@0.050"
Edelbrock headers
Stock Electronic Q-jet
Stock alum intake

 

Replace those Plat 4's with regular spark plugs. They cause all sorts of weird problems, especially with EFI.

 

rod - I think your problem is somewhat different, perhaps you should start a thread of your own.... (Is this in you Monte?)
Welcome to the boards though, hope Edmonton is as nice as Cowtown now

Adam, I think you're confuzzled, rodss has platinum plugs, but a q-jet... However, i'd agree anyway, platinum plugs are meant to stay in the engine for a long time, good for a car that's a pain to get to the plugs, not good for performance... use copper.

89IROC - maybe the TPI board is more appropriate? If it's a computer problem at least...

 

If they are the +4 plugs, the ones with 4 electrodes (or even the ones with 2), then he should toss them. I used to work at a parts store that sold them, and NO ONE that bought them liked them. They did nothing but cause weird running problems. They changed back to normal copper plugs and all the problems that started when the +4 were installed immediately went away. Beleive me, they cause lots of weird running problems.

 

Ok...I was thinking about swapping those Plat 4's out anyway...what a ****-off, very expensive!!

Thanks guys....generally the engine is performing great. The Herbert Cam sounds really good and pulls 15" of vac. I built a voltage booster to install on the vac sensor since I'm just under the recommended voltage for the ECM...I'll let you know how it turns out!!