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GM Bob
GM Bob, ASE Certified Technician
Category: Chevy
Satisfied Customers: 963
Experience:  30 plus years. experience as GM technician, ASE Master Technician and GM Certified.
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I have a 1999 chevy Blazer it starts all right but during

Customer Question

I have a 1999 chevy Blazer it starts all right but during acceleration it stumbles , jerks , the tachometer drops down to about 400 rpm but does not completely die . The tach. comes up when you let off the gas .It does this in cool weather fall and winter not so much in spring and summer , it goes away after engine is completely warmed up .
JA: Has the vehicle turned into a gas hog? And how does it start -- same as usual?
Customer: No its does not use any more gas than usual . it starts fine .
JA: Are you fixing your Blazer yourself? What have you tried so far?
Customer: I have taken it to a dealership and two other smaller shops they say it does not do it for them , It has no check engine lights . I bought a scanner and it shows no codes .
JA: Anything else you want the mechanic to know before I connect you?
Customer: I have changed the throttle position sensor and the MAP sensor in the intake manifold so far.
Submitted: 28 days ago.
Category: Chevy
Expert:  david craig replied 28 days ago.

Hi Im David, thanks for visiting the site. removed and clean the heck out of the iac and egr and their passages. brake cleaner does better than anything. the using maf sensor cleaner clean the sensor wires for the mass airflow sensor. you will be good to go.

Expert:  david craig replied 27 days ago.

checking in to see how its going

Expert:  david craig replied 26 days ago.

do you still need assistance?

Expert:  david craig replied 25 days ago.


Customer: replied 24 days ago.
I finally was able to find the answer , I read it . and I have not tried any of the fixes yet. I was having trouble with the billing part of your site , I am not really sure what I owe or if I owe .
please let me know about the billing part . I will try the fixes you suggested soon , Thank You .
Expert:  david craig replied 24 days ago.

you dont owe anything until you are satisfied with my assistance. so until you try my suggested fixes, we wont know.

Expert:  david craig replied 23 days ago.

please accept the answer and leave a 5 star rating if you were satisfied with my assistance. thank you

Expert:  david craig replied 22 days ago.


Expert:  GM Bob replied 21 days ago.

Hello my name is Bob.

Do you still need help?

Customer: replied 20 days ago.
I have been to busy to try the fixes yet , I will try them soon.
Expert:  GM Bob replied 20 days ago.

Thank you for getting back with me.

After you clean mass air flow sensor. It may run a little better. If so my have to replace it.

Expert:  GM Bob replied 14 days ago.

Do you need ant more help?