jeremyw2585

I just put the motor back in my car a week or 2 ago. It has been running and driving great until the other day when it just suddenly started bogging really bad and backfiring a little. It feels really weak until I hit wot and it seems to clear up for a sec. until I let off. Even while it is idling it sounds weird (not missing). Even when I hit the throttle in park it bogs really bad. I have new ac delco 02 sensors and there is no exhaust leak. I unhooked the maf and it didn't change. Could someone help me figure this out?

SnakeSkinner28

Check for a vacuum leak, arching wire (might have a wire near the header or something), is it throwing a code? Check the O2 sensors, could be the opti crapping out, there are a lot of possibilities especially if you just put the motor back in...

jeremyw2585

I checked for vacuum leaks and burnt wires. I will check to make sure all the wires are snap on the plugs and opti. No SES light.

SnakeSkinner28

what year is the car? stock motor? how come the motor was out etc...i guess more info the better since this problem could be a sh!tton of issues...

jeremyw2585

It is a 94 z28 with heads and cam. I pulled the motor to build the bottom end up. Also right before it got really bad it would only bog down when I hit the throttle fast. If I eased the throttle down it wouldn't do it. I have a descent sized cam in it and now you can't even hear it. It has a lope, but a different kinda lope than the cam makes.

jeremyw2585

Another thing is that since I put the motor in the fans have not came on. I had to wire a manual switch.

SnakeSkinner28

Have you gotten it tuned??

jeremyw2585

Yes it has been tuned. I don't think it is a tuning issue because it happened just all of the sudden. First it had a little bog and then I hit wot (not for the first time). Let off and it went crazy. I have been thinking and I am gonna clean the MAF and change the temp. sensor in the water pump when I get home from work.

93FIRETURD

Check your fuel pressure if the pump went bad you would have the said symptoms. Good luck!

jeremyw2585

I hope it is not the pump. It is a brand new walbro.

Hal Fisher

I think bogging is always fuel. Use the "trap door" method for replacement. If it's new than it should be under warranty.

Hal

Venomous360

Mine is doing the same thing, I think mine is the Opti going to swap it out this weekend.

jeremyw2585

The SES light finally came on today. It read code 26 (output drive module). I think this has something to do with the ecm. Could someone with experience help me out with this?

jeremyw2585

Checked fuel pressure. With key on car off it is 40 psi. With the car idling, or reving it stays 45 psi.

WhiteThunderZ28

It could be your IAC... I had the same symptoms when I installed my cam... It would miss and backfire, so I put my old IAC back in and the car ran fine. Ended up that my IAC was able to move around in the housing that it was secured in... I almost thought it was the opti since it sorta has the same symptoms when it goes.

See if you can borrow somebodys IAC just to make sure.