Hey guys i just recently got my car up and running good again. Just replaced the timing set, crank sensor, coil packs, and ignition module. Anyways i took the car out for a drive and when i go WOT and the boost builds up the car backfires and looses power instantly. Any ideas of what could be the problem? I replaced the plugs not to long ago, and the plug wires are some from Kirban. Also i do not have the air filter on right now (this was a short drive mind you). Thanks
Backfire at WOT
- Thread starter TrAb
- Start date
Welcome!
By registering with us, you'll be able to discuss, share and private message with other members of our community.
Were you running Alchy?Ok i should have specified on my mods. All that is done to the vehicle is 3in catless exhaust, 38lb injectors and FMIC. Everything else is stock, the MAF is stock i just took out the air filter canister while waiting on the LS1 maf to come in. So it just has the 90 degree bend right after the stock MAF.
turbojay
Active Member
- Joined
- Feb 14, 2009
- Messages
- 953
Vacuum leak?
You think there could be a vaccum leak with the FMIC piping i put on? Ill try to look it over when i get home. Or better yet i may slap the stocker back on and see if the problem continues or not.
How do i ohm the plug wires?
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
- Messages
- 9,478
You sure you have the cam sensor set right? How did you set it?
Car run good before the timing set, etc replacement?
I came home tonight and put the factory air box on and it didnt make a change, well made it idle a good bit better
...Yes car was running fine before i replaced those. I have the caspers cam sensor tool, where you plug it in and twist the top until the light turns on. Although when i put the sensor down into the front cover i am not sure if it was exactly right or not. In the intrustions with caspers tool it just says that the cap should be just a tad after the 3 oclock position so thats where i tried to get it close to.
Robert Wilson
Member
- Joined
- May 26, 2001
- Messages
- 485
If you still have a problem after you have done the other suggested checks, check every spark plug for a cracked or broken insulator. I had experience with a car that idled and drove fine under normal driving conditions but under WOT would miss and backfire. Ended up being a broke spark plug insulator. The owner never thought this could be the problem because he had recently replaced the plugs.....
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
- Messages
- 9,478
I came home tonight and put the factory air box on and it didnt make a change, well made it idle a good bit better
Yes car was running fine before i replaced those. I have the caspers cam sensor tool, where you plug it in and twist the top until the light turns on. Although when i put the sensor down into the front cover i am not sure if it was exactly right or not. In the intrustions with caspers tool it just says that the cap should be just a tad after the 3 oclock position so thats where i tried to get it close to.
Factory air box? Did you mean the factory MAF?
There is more to the sensor than just turning the cap in reference to where you put the sensor in at.
The engine needs to be at a certain place in the cranks event cycle, degrees marked, etc. Your description of the cam sensor adjustment leaves alot to be questioned on whether the items are set and installed correctly.
If the cam sensor is installed poorly and or leaks in the intake system post MAFthen they could cause issues that you described.
the cam sensor can be a bit tricky to get aligned sometimes
Do you have a link to a guide? But what i did was put the engine at TDC, drop the sensor in as close as i could get it to 3 oclock. Then turn the engine backwards the 25 degrees or whatever was specified, then set the cap.
- Joined
- Aug 1, 2003
- Messages
- 9,610
zero on the compression stroke of #1 cyl then rotate crank clockwise 1.45" (25After TDC #1 comp), then set sensor by tuning clockwise until light comes on then goes out then turn it counter clockwise until light comes back on , clamp it down
the procedure its pretty clear and by now im sure youve been told where to go for info and to read up
steve woods site, specifically .. http://www.vortexbuicks-etc.com/cam_sensor.htm
last time im going to offer advice ...read or learn to use the search feature
only about a hundred threads on how to properly set the cam sensor here
for those that wan to guess here a link to where he came from and where its at so youll be brought up to speed as far as whats what on his car .. http://www.turbobuicks.com/forums/buick-v6-turbo-tech/88432-bought-gn-broke-down.html?highlight=trab
the procedure its pretty clear and by now im sure youve been told where to go for info and to read up
steve woods site, specifically .. http://www.vortexbuicks-etc.com/cam_sensor.htm
last time im going to offer advice ...read or learn to use the search feature
only about a hundred threads on how to properly set the cam sensor here
for those that wan to guess here a link to where he came from and where its at so youll be brought up to speed as far as whats what on his car .. http://www.turbobuicks.com/forums/buick-v6-turbo-tech/88432-bought-gn-broke-down.html?highlight=trab
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
- Messages
- 9,478
The vague post of how you do things doesnt give much for us to work with. When you say thisng like "I came home tonight and put the factory air box on and it didnt make a change" and "Although when i put the sensor down into the front cover i am not sure if it was exactly right or not."
Reading that kinda stuff questions your ability. Not saying you cant do it ..Just when asking stuff be a little more clear on what you did.
As I asked you before...... what was the deal with the factory air box reinstall?
Reading that kinda stuff questions your ability. Not saying you cant do it ..Just when asking stuff be a little more clear on what you did.
As I asked you before...... what was the deal with the factory air box reinstall?
Sorry for being vauge. While i was waiting on getting a LS1 MAS i took the factory air canister off and left it off the vehicle. This just left the stock MAS on the car and no air filter. So i was just test driving the vehicle this way. I was just saying that last night i put the factory air filter/canister back on the car as i was uneasy about driving around to much with any filter at all.
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
- Messages
- 9,478
You REALLY need to do your homework on these cars.
Lesson 1 grasshopper...MAF (not MAS) Mass AIr Flow sensor
Does your stock MAF have any screens in it?
How did the cam sensor check work out?
Lesson 1 grasshopper...MAF (not MAS) Mass AIr Flow sensor
Does your stock MAF have any screens in it?
How did the cam sensor check work out?
bmackinnon
Active Member
- Joined
- Feb 24, 2005
- Messages
- 2,092
He has a LS1 maf... nobody has mentioned the possibility of the car going lean and backfiring... that's always the 1st thing I check, as the consequences are by far the most expensive....
are you sure the fuel pressure is correct and rising 1:1 with boost?DailyDrifter
The Slow and the Curious
- Joined
- Dec 5, 2007
- Messages
- 5,118
He has a LS1 maf... nobody has mentioned the possibility of the car going lean and backfiring... that's always the 1st thing I check, as the consequences are by far the most expensive....
+1
Op did the car backfire from the intake or exhaust?
