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Super Mechanic
Super Mechanic, Master technician
Category: Chevy
Satisfied Customers: 17219
Experience:  29 yrs. exp., ASE master, cert. in G.M. electrical, a/c, susspension, brakes, electronic steering
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Buddy backfireing throught the throttle body, i can see

Customer Question

hey buddy backfireing throught the throttle body
JA: Where exactly do you think the noise is coming from? And how long has this been going on?
Customer: i can see sparks in the tb
JA: What is the model/year of your Chevy?
Customer: i had the tranny rebuilt ran great for about three weeks and this is goinegon
JA: What year is your Chevy?
Customer: 95 geo metro
JA: Are you fixing your Metro yourself? What have you tried so far?
Customer: new distraber timming belt
JA: Anything else you want the mechanic to know before I connect you?
Customer: also had a ground issue wound not turn over noticed that the enginf mount was apaskinf
Submitted: 10 months ago.
Category: Chevy
Expert:  Super Mechanic replied 10 months ago.

Hello and welcome. My name is ***** ***** you for visiting the site, I am reviewing your question and will reply shortly, thanks.

Expert:  Super Mechanic replied 10 months ago.

What is the compression in the cylinders?

Does it back fire at idle or under a load?

What is an engine mount apaskinf?

Customer: replied 10 months ago.
compression 75 to 80 per cylinder
backfires underload
Expert:  Super Mechanic replied 10 months ago.

I see, thanks.

We, (the experts) are only paid by your positive ratings.

The compression is way too low, possibly valve seats on that one but could be the rings/cylinders. However, normally a back fire under a load is from low fuel pressure, whereas a back fire, (out the intake) at idle is a burnt intake valve.

You can tell if the back fire is constant and sort of rhythmic, that's a valve and when driving, it has a sporadic pop as you try to go faster.