This is on my wifes 2.8L MPFI. Her engine died at 180k miles and she refused to let me put in a bigger motor. So I ordered a new crate 2.8L motor. Replaced all the sensors and injectors including cold start injector. Replaced thermostat hoses belts, distributor. Pretty much everything. So I finally got it all together and fired it up. I wanted to run it 30 mins at 3000rpm to make sure and break in the cam. BUT after about 5 minutes the exhaust was glowing red to the point that the antiseize compound that I used on the bolts holding y pipe to the manifolds caught on fire. So I was forced to shut her down. I though that it could be the timing or the computer just hadn't relearned the new motor yet. So I restarted the car after it had set about 10 minutes and set the timing at about 25-30 degrees (computer still controlling at this time) and retried the 3000 rpm run. Same problem. I did not have any lean running problems before the motor install. What is the problem. The computer is not throwing any codes saying that it is running too lean. I put a nice new bosch o2 sensor in it. The motor sounds great but I have to get by this exhaust glowing problem. Is my cam screwed now because I couldn't make her run 30 mins.

 

Did your catalytic convertor somehow get clogged up? The timing could be way out of spec, too... could you:

1. Spin the engine so the balancer mark for #1 is at 10 deg advance mark
2. Align the rotor to the cap so the rotor's aimed at the #1 plug terminal

Wouldn't that give you the 10 deg advance the motor calls for?

Don't know about the cam...


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
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