What would cause the car to immediatly backfire through the intake while cranking. It seems to do this every time. I did a cam install months ago and still have a car that doesn't move.

 

Anyone? I have heard overtight rockers can cause this. I really don't think so in my case though.

 

Did it have the problem before the cam install???

 

Nope, it happened once before the cam install but that was because of a different problem. I am just trying to narrow it down so I know what I should be looking at.

 

You either have the cam timing off, or you have the ignition timing off by installing the opti wrong. The cam timing is easier to test for than the ignition timing. Try doing a leak down test first if you can get to the plugs. Since you didn't have the year in your signature, I'm guessing you have a 93 or 94. These seem easier to miss the ignition timing when installing the opti then the later ones. It's a toss up between the 2. If you feel the the valve timing is right on, then put #1 on TDC and remove the front of the opti and see were the rotor is facing. You will need a deep torx female socket to get the cap off the opti.

 

I am almost positive the cam timing is right on(checked it twice). I am going to try exactly what you said, I posted awhile ago and as I remember the rotor should be at the 6:30 postion when #1 is at TDC. Could there be any other causes if the timing is as it should be?

 

There are other causes but they are remote. Also one thing you have going for you is that you took it apart and after reinstalling it, whamo, no worka. Usually when a backfire occurs, it's because of timing. The 2nd most often cause is fuel but you didn't mess with that.

Check the inside contact like I mentioned in the PM and you should find your problem. BTW was I right that you have a 93 or 94???

 

Yep, its a 93. I actually hope I put the opti on wrong(easily fixed). I am going to give it a try today I think. Thanks

 

Well I checked the ignition timing today... it was right on. I also reajusted the rockers while I was at it. I found that I had overtightened the intake valve on #7. My intake backfire has gone away(I assume #7 was causing it) however I still have no start.

 

Time for a refresher course on basics. Check compression and check spark at all the plugs. Double and triple check plug wire routing. Then check fuel supply.

 

I have checked the wires they are definitly routed right. One of my wires is junk(no spark) I am waiting for a new set to come in. I checked compression on a few cylinders they were all ok. I couldn't get to most on the passenger side though. I checked fuel pressure awhile back and got between 38 and 45psi.

 

Is one of your wires bad or all of them. Is it a bad wire? Maybe its the opti. When my opti went out it wouldnt start, just make noises and sometimes act like it wanted to start. Check for spark on all the wires.

 

The opti is brand new, I was also fooled into thinking it was the problem. Although the old one was sort of rusty on the inside. Nope its just the one wire that has no spark, it's the wire trust me Although from what I am reading the car should still run somewhat on 7 cylinders. Can't be helping thats for sure