Cutting out high rpm/MAJOR backfire

[jbud1291]

Hey all...so about two weeks ago my car started acting up, bogging out, misfiring, all that good stuff the we love. So i went ahead and got new plugs, wires, cap and rotor for the disty, and while i was at it i bought a new fuel filter, pcv valve and ckeaned out the TB...anyways under WOT around 5500rpm it starts to cut out and choke quite a bit, also when shifting 2nd to 3rd under WOT it violently backfires and i mean it shoots a 2ft flame and the bang that it makes rings my ears lol

So im guessing my ignition timing is off. My question is when adjusting it do i want to turn it up or down? (meaning when i loosen the bolts on the disty do i want to bring it up or down).

Also, ive recently had a test pipe installed as well a decrease in mpg, so maybe 02 sensors? Any input appreciated, Thanks!

[mitmaks]

I would put your stock exhaust back on and start from there. You can rent timing light from most auto part stores.

[jbud1291]

The car came with a custom 2in and a magnaflow muffler..i threw the test pipe on because i had one laying around and the packing in the cat fell apart and was clogged up pretty bad i was surprised the car was still running witj how bad it was...but okay cool ill look into that thanks

[WhiteFinish]

You'd need a timing light and than start adjusting.

Don't forget to put it in diag mode.

[jbud1291]

Thanks ill remember that....do i want to advance the timing or retard?

[Redline322]

Just check your timing marks first, make sure at the crank it is good and you can also try adjusting your ignition timing by moving the disty back and forth. By the sound, you might need to advance it slightly. Make small adjustments until you find the sweet spot.

[mikeetown]

Are you burning any or a lot of oil?
Definitely get your car timed first.

What codes downpour CEL show?

[jbud1291]

Thanks for the input guys...well i havent gotten the car plugged into to see what codes come up...but the CEL light is not on

[Daninski]

If the CEL isn't on you have no codes. Usually putting the disty in the middle of the adjustment slot is close. Jump TEN and Gnd in the diagnostics box make sure your timing is set to 650 then set your timing. Is there any chance your valves could be burned? They would then leak and cause backfiring. Do a compression test to check if the valves are still sealing. I blew a muffler right off my car once because my valves were shot. lol

[jbud1291]

If the CEL isn't on you have no codes. Usually putting the disty in the middle of the adjustment slot is close. Jump TEN and Gnd in the diagnostics box make sure your timing is set to 650 then set your timing. Is there any chance your valves could be burned? They would then leak and cause backfiring. Do a compression test to check if the valves are still sealing. I blew a muffler right off my car once because my valves were shot. lol

Lolol it sounds like its gonna blow my muffler off...not sure if they,re burnt but im gonna take a look this weekend so ill keep u guys updated. Thanks!

[Daninski]

Do a compression test and leak down for sure.