Need help with troubleshooting: engine bogs
Need help with troubleshooting: engine bogs Car was running great after a recent dyno. But since Sat the car will "bog" for a split second during normal driving.Almost like all power is lost for a 1/4 second each time. I have a scanmaster and there are no codes. The only odd parameter I can see is timing will momentarily jump from say 35 degrees to 25 degrees during these "bogs". I cant tell if its the pulling of the timing thats causing the bog or the bog making the computer pull timing. It does NOT do this during warm up cycle as far as I can tell.
Only things that have changed since the car was running good was I put in about 7 gallons of VP 104 octane. I may have bad gas...I got it from the local track, it was in a barrel that had only 1/4 left nd there was a huge rainstorm that night. So contaminated gas is a possibilty
Other item was I blew a fuse after tapping into an unused wire that would normally go to the traction control switch. It popped the fuse that controls the guages and auto headlight on. So electrical damage/computer may be a possibilty but unlikely
Other items I can think of off hand are:
* 02 sensors...already been swapped
* crank position sensor..havent tried that yet
* reluctor wheel like PSJ's old motor, but I would think it would do it on startup as well
* Computer...I hope not
* harness...I hope not
Any other ideas? I am in the process of draining the gas and putting in some fresh 93 right now
Only things that have changed since the car was running good was I put in about 7 gallons of VP 104 octane. I may have bad gas...I got it from the local track, it was in a barrel that had only 1/4 left nd there was a huge rainstorm that night. So contaminated gas is a possibilty
Other item was I blew a fuse after tapping into an unused wire that would normally go to the traction control switch. It popped the fuse that controls the guages and auto headlight on. So electrical damage/computer may be a possibilty but unlikely
Other items I can think of off hand are:
* 02 sensors...already been swapped
* crank position sensor..havent tried that yet
* reluctor wheel like PSJ's old motor, but I would think it would do it on startup as well
* Computer...I hope not
* harness...I hope not
Any other ideas? I am in the process of draining the gas and putting in some fresh 93 right now
Re: Need help with troubleshooting: engine bogs I've had some hesitation in my car since the weather started getting warmer. After I dyno-tuned this past weekend everything was fine the remainder of the day. All the following day I was getting stumbling and hesitation. Logs indicated random surges of KR and my MAF frequency dropping to zero during driving.
I eventually threw a P0102, so I reset the MAF connector. I also noticed my Lid <-> MAF band clamp was a bit loose and I tightened it. Everything has been fine since.
Good luck!
I eventually threw a P0102, so I reset the MAF connector. I also noticed my Lid <-> MAF band clamp was a bit loose and I tightened it. Everything has been fine since.
Good luck!
Re: Need help with troubleshooting: engine bogs Found it! 
I drained about 90% of the gas out and disconnected the MAFT. I was going to go get 5 gallons of 93 but I decided to start it first to note any differences. Didnt have the miss. Went ahead and drove to the gas staion...no misses or stumbles. Filled up with 93 and went for about a 15 mile drive...no misses or stumbles. Went home and shut the car off...hooked the MAFT back up and started it...immediately began to stumble. Disconnected MAFT...ran fine. So my MAFT took a ****. At least its no my computer. I thought it was logical it would either be MAf or 02 related since they are not refernced by the computer during start up/warm up.
So anyways...Im back in business...thanks for the replies guys
I drained about 90% of the gas out and disconnected the MAFT. I was going to go get 5 gallons of 93 but I decided to start it first to note any differences. Didnt have the miss. Went ahead and drove to the gas staion...no misses or stumbles. Filled up with 93 and went for about a 15 mile drive...no misses or stumbles. Went home and shut the car off...hooked the MAFT back up and started it...immediately began to stumble. Disconnected MAFT...ran fine. So my MAFT took a ****. At least its no my computer. I thought it was logical it would either be MAf or 02 related since they are not refernced by the computer during start up/warm up.
So anyways...Im back in business...thanks for the replies guys
