I started my 3.4 for the first time today. After about a minute the exhaust manifolds started to glow orange so I shut it off(I hope this doesn't screw up my cam break-in). I had my timing set by turning the motor by hand until it was at TDC, then put in the distributor with the rotor pointing at the #1 cyl. I replaced all the rubber vacuum lines and replaced the plenum vacuum lines with some Dickman lines. Can the exhaust clog from sitting for awhile? I have a Dickman cat converter and original muffler. Is it safe to run the engine to re-check timing in this condition? I'm worried I might break something with the engine being so fresh(it's a Grooms rebuild).

Ok. I timed the engine at 10* BTDC with the paper clip in the computer connector. I checked the vacuum lines again. Now only the front manifold glows. What is going on?

You have to be absolutely sure that you connected all the vacuum hoses to the plenum. Look under the plenum and don't forget the pipe that connects to the throttle body, those are easy to miss. If you had disconnected the battery, the ECM will be in a learn mode and will run the engine rich for a while as it learns. Do you have a high idle? (@2000rpm's or more) This would definitely be a sign of a vacuum leak, the engine will also sound abnormally loud. Hope this helps a bit.

------------------

It idles around 1800-2000. I'm gonna check my vacuum lines again, and if I can't find a leak, I'm gonna replace the rubber boots. I've also timed the engine using a vacuum guage. No real difference. I took it around the block with my girlfriend watching the manifolds and they didn't glow during normal driving. I'm worried about interstate driving.

When I broke in the cam in my motor, the manifolds also glowed red. I think it may be the result of running the motor at speeds without any airflow over the manifolds to cool them off. It could also be an indication that your motor is running too lean or the timing is way off.

Farknocker

I re-timed the engine using the timing light. It now idles at 800-1000, right where the 2.8 used to idle. I had the timing set using a vacuum guage before. I think using the light is better. Do everyone's manifolds glow at high rpm while the car is stationary?

I don't remeber mine glowing on my 3.2's break in. just the oxygen sensor screwing up. Damn check engine light kept coming on.