I have a 1999 chevy lumina with 190,000 miles, 3.1, v6, auto trans. the problem is that it will run great for a while and then start to stall and buck and hestiate. I have had the 02 sensor, egr, ingition mod., plugs, wires, all changed and same problem. I thinking ecm. Does not matter hot or cold it will run then sound like it is missing but will push past for a while, this is at any speed. Any ideas???? I need help this car is driving me crazy and broke!!!

Thanks.

Did you check to see if there were any codes? Some of the national brand autostores will check codes for free.

You didn't say anything about the fuel system, can you check fuel pressure? When was the last time you changed the fuel filter? Make sure there is no pressure on the lines, if you take anything loose.

Yes i had the fuel pressure checked and it was at spec and the codes keep jumping around first it was egr then ingition then o2 very confusing.

Yes i had the fuel pressure checked and it was at spec and the codes keep jumping around first it was egr then ingition then o2 very confusing. also changed fuel filter.

What were the code numbers?

I have a 1999 chevy lumina with 190,000 miles, 3.1, v6, auto trans. the problem is that it will run great for a while and then start to stall and buck and hestiate. I have had the 02 sensor, egr, ingition mod., plugs, wires, all changed and same problem. I thinking ecm. Does not matter hot or cold it will run then sound like it is missing but will push past for a while, this is at any speed. Any ideas???? I need help this car is driving me crazy and broke!!!

Thanks.

check all wires going to ground esp. ecm wires and connections repair any damaged wires loose rusted ground lugs fasteners.......this is because codes and failure not consistant

Hello,

I have a 97 Lumina that does the exact same thing. I had everything checked, come to find out it was the catalytic converter. Have that checked. Any auto shop should be able to do it. Good luck with that. :2cents:

I have a 1998 Lumina with 82k miles, last year the Intake Manifold gasket started to get leaks in it and engine oil was getting inside the radiator.

From what I have heard this is a common problem for a lot of Chevrolet's and the place I took it too says they do these often. I would check your radiator, see if it has oil deposits in the overflow reservoir. When I had it happen to my car, Cylinder 1 and 4 had issues with misfiring so my accerlation lagged, starting was a problem sometimes. Does it have a hard time starting sometimes, not turning over but just engaging period?

It cost me about $700 to get it fixed, tuned up, replaced the gaskets, and flushed the radiator. I hope this is not the issue with yours but if it is be ready to spend some money.

when you turn the key on, but dont start the car, does the fuel pump make a funny noise? I would think it'd be the fuel pump b/c thats what's happening on my '99. Fuel pumps for it run between $300-$400.

Welcome to AF, the pump runs for 3 seconds or so when the key ign is first turned on, if the pump is noisey either the filter is clogged or the pump is going bad. BTW in the future start a new thread this is way too old, thanks.