Pontiac Problems? Ask a Mechanic for Answers ASAP
Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.
When you say it cuts out at 40 mph is it misfiring or shutting down?
Have you had the fault codes checked/read out at all to see what codes are set with this issue here?
Let me know,thanks Pete
Is or has the check engine light come on or started to flash at all with this issue and have you had the fault codes checked at all?
O.k.,the first thing that needs done here is to have the fault codes read out to see what codes are set.This can be done for free usually at a local parts store.If you can get the codes read out and post the code info here this will help with this fault.
I have seen the crank sensor cause this type of issue with the misfire and stall out at low rpm and no start until it sits a few minutes.I have had to replace this sensor several times before.I have also seen issues with the throttle body bore being dirty needing cleaned.You might take a shop rag and spray it down with carburetor or brake cleaner and wipe out the throttle bore to see if this resolves the fault.But if you can get the fault code info to me here on this post this will help.Even if the light has been on for some time you may have new codes set for this issue that is occuring now.
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