[jamiep]

I just performed a valve stem seal replacement (and front main seal), now the car will not start. It tries, then backfires. Any ideas what may be wrong?

 

[Bill P]

First guess, you're off a tooth on one of your cam gears. I would recheck the timing.

 

[cord4530]

Totally agree with Bill P.

The second guess would be to check the ECU for a code 12 - or other code that points to the crank sensor.

 

[InTheRed]

Cam timing is the only thing that it could be if it backfires...

 

[jamiep]

Well, I also installed a BL fuel system at the same time. I pulled the code. It shows "78", which is a "fuel pump control signal". I am not sure if that would cause the problem or not.

 

[BlitzTT]

Timing is your problem on the back firing most likely.... code 78 weird part is it's probably your coil pack connection....

 

[jamiep]

It turned out that the crank position sensor ring came off of the timing belt pulley. Apparently this is common?!.

 

[cord4530]

Woo Hoo! 2 points for me.

This is pretty common on our engines. Well, common enough that it's happened to several people anyway. Especially any time you're working in that area (timing belt, front main seal, etc.). Sorry to hear that it went out on you, but at least you know the problem now.

The common thing to do is have the ring tack welded to the pulley. Apparently the replacement part isn't all that expensive, but it's not fun to deal with since you were *just* in there and now have to get back in there again. Here's a small thread on the topic:
http://www.supraforums.com/forum/showthread.php?t=132054

 

[InTheRed]

:urowned: Never heard of that before! Be sure you get it tacked back in the exact spot!

 

[Gadfly]

Get a new ring, and have it welded to the gear. I had this done last time I changed my belt, just to be safe.

 

[93civEJ1]

hey Jamie.....how hard was the stem seals? I need this done on mine too, and definatly the front main....im about to do the rear main cause im dropping the tranny.

 

[$9ktt]

We just did TWO supras this weekend !!!! First time EVER doing any cam work !!!
This job is CAKE !!! Just follow the how-tos out there. And get the TSRM or
download the parts for t-belt , and cam install. Needed that for torque specs.

Time consuming, that's all. Get that Toyotool combo tool, and use a rope.

GL

 

[93civEJ1]

We just did TWO supras this weekend !!!! First time EVER doing any cam work !!!
This job is CAKE !!! Just follow the how-tos out there. And get the TSRM or
download the parts for t-belt , and cam install. Needed that for torque specs.

Time consuming, that's all. Get that Toyotool combo tool, and use a rope.

GL

nice...so cake, you mean....how much money and down time are we talking?? I need to do this myself...but when I get around to it, I figure I might as well slap some cams in it at that time too...I see 272's in my future one day.

 

[$9ktt]

Yeah, that's what we did to ther other car. 264's, PHR springs,and Titan cam
gears.

It'll take ya 9-10hrs. continous workin. $300-600 for cams, $400-500 for gears .
These are used/new prices. I would have done them too. But I'm only BPU, and
got other issues to deal with first...