Another check engine light question

[lizineauclaire]

I just bought a 94 Grand Am, 3.1. I know it needs a tune up which will be done as soon as I find a decent mechanic. This is the weird thing. It runs awesome but when I go over 60 then hit the brake the check engine light comes on. That's the only time it comes on. After I shut it off then restart it the light goes off. I have always owned GM cars but have never had this problem. I love my car!! It even started right up after sitting for 3 days in some below zero weather we had 2 weeks ago. Thanks for any help.

[GTP Dad]

Welcome to AF!!

The only thing I can think of that would cause this would be a voltage draw when you hit the brakes causing a reduction in the amount of voltage to the computer or a vacuum leak that is causing the emissions system to malfunction. I really don't know what else could cause it. Maybe someone else would have an idea.

[loridingt98]

i have this same issue right now, i have a scanner and it always comes up with code p0401, egr flow insufficiant (sp), likely a bad egr valve or carbon buildup from egr passage going to air inlet after the throttle body,i am going to try and get the carbon out this week and see if that solves the problem, also car has noticable smell of exhaust fumes sitting at red light, stop sign,ect. car is a 98 grand am gt, 3100 v6, 156k on the clock

[xeroinfinity]

loridingt98, clean that passage out and it should return to normal, unless the Egr its self it defective.

And lizineauclaire, I would suggest that the next time the service light comes on, go get the code read and see what it says.

[lizineauclaire]

Hi all, sorry it took so long to reply. Ok, took the car in to a mechanic today. I already knew it needed a tuneup which is what he said. He took the car on the highway then off to get the light to comeon then put it on the computer. He did not tell me what code came up but told me I need a EGR Vacuum solenoid then quoted me a price of $497.92 & $56.00 for labor. Well, I went to Rockauto.com & ordered the same part for $165.00. Now here's a good question. Someone told me to get some Seafoam, unhook the big vacuum hose that goes from the EGR thing to the intake manifold, pour some Seafoam in there, hook it back up & run it. He said that should clean all the gunk out of there as well as clean the intake & all whatever else it would run to. Has anyone ever tried this or heard of it?