engine died 78mph

[bigbrown]

man i hope i'm getting to the end of this "getting the bugs worked out" thing.

here's what happened...

put a nappa smog pump on 2 days ago. seemed to run great. so great that i decided to take it up to almost 80 mph (3400rpm). i don't really know why. feeling cocky with all my tuning i guess. then it just died. i coasted to a stop and it started right up again.

problem is, now it won't idle below 1100 rpms. it just dies.

i checked the timing thinking maybe the new air pump threw it off. it was advanced quite a bit. i set it back to the mark again.

oil looks good, no water.

water looks good, no oil.

pulled each spark plug while running one at a time. they appear to all be fireing.

vacuum gauge reads 18 until under 1100 rpms as it dies.

i'm spraying the heck out of the vacuum lines with soapy water to find a leak but nothing.

i have a new egr on there and pcv.

it doesn't sound terrible now but i might be hearing a subtle thumping noise like a little backfire or something while it's running. not bad though.


i've done so much work on this by myself that i hate to give up now and take it to a mechanic. it's a pride thing....oh, and money

ideas?

thanks a ton guys,
andy

 

[Heffenoche]

Don't know if this is the problem but the idle selenoid on the carb can cause this problem when not working or not grounded properly.

 

[3puttcop]

Sounds like a fuel/carb problem. Check your fuel filter.

 

[bigbrown]

i'll check the fuel filter. it's only a couple weeks old though. it just seems weird that it ran so well then the minute i push it harder than i usually do. this happens. like i broke something.

i'm just staring at it with the choke on and it sounds noisy and rattleing a bit around the carb area. hard to hear as it's so freakin windy right there.

 

[3puttcop]

The filter may not chage your idle speed up but may cause shut down at high speed. Prob a carb prob.

 

[BlueCruiser84]

fuel cut solenoid on the carb...the little green connector on the top. Search the forum for it there is lots of info.

Brian

 

[NocalFJ60]

If it runs sluggish the EGR valve might be stuck open. Put a short hose on the top of the EGR valve and blow. When I installed a new EGR valve it got stuck the first time it opened all the way. The high vacumm going 80 might of sucked the valve up to its limit.