I have the LE 1 heads/cam package with 42 lb/hr SVO injectors, once this went onto my car it was ran for 30 minutes with stock programming. Then this car was physically driven around the block a few times to make sure everything was in good working order. After this the plugs were all fouled out due to it running way too rich, as 93s with stock programming do, so the plugs were cleaned and a switcher chip was installed the car but it was on the wrong bank, so the car was pretty much ran in fail safe mode (when the SES light comes on and the fans kick on, etc..) but I was told that this car was driven after this. (This was all done by the engine builder on the car and is just what I was told, besides the car going into fail safe mode, which I just figured out on my own.) Now I have found the banks that the programming is on from the mail order tune and after cleaning 5 out of the 8 plugs and reinstalling them (and at this point I have put the stock 24 lb/hr injectors back in, because I wanted to make sure that those used injectors I bought were just stuck open) I tried to fire it up last nite, the car did fire on the 5 cylinders for about 5 seconds, but was still running rich and the car just backfired hard out the exhaust this time. Then I tried it again and it fired again but it only ran for about 2 seconds and backfired through the intake. This went on a couple more times and then I pulled the elbow off and there is gas all in the throttle body. This is quite confusing to what is wrong with the car here, if the programming is fine as of now, that should mean the a/f should be OK and runable (at the least), It seems like the timing is off, causing the backfiring and stalling out, but if that is the case, how was it possible for the engine builder to physically drive the car a few times, and also run the engine for 45 mins? Another thing i'm not quite understanding is why I can't even get the RPMs up once it fires, cuz soon as it starts and jumps to about 1100 rpm, a couple times I tried to give it some gas and the car didn't rev at all, but instead just backfired even harder and stalled the car out. I pulled a plug out and it came out completely black and soaked in gas, similiarly to what was happening on stock tuning. The other thing I was thinking about was maybe it is the fact that it is missing on the other 3 cylinders, but shouldn't the engine run on the other 5 cylinders? Reason I didn't clean all the plugs out is because they keep fouling out right away and I was hoping that it would run on the 5 cylnders enough that I could drive it into the garage where I could actually jack the car up, as of right now it took 4 of us and a running start from the other side of the street to push the car up onto my driveway (my driveway is a good 65* upward incline) and I can't jack the car up on my driveway on this incline...

 

What I really don't understand is how the engine builder actually drove the car... To remove/install the 2 rear plugs on the groty LTs (what I have) you have to remove the header, so that you can remove the starter (they hug the starter) so that you can reach up and at the spark plugs and I know for a fact he didn't take this much time to clean the plugs (he prolly did that about 8 times) meaning he had it going on 6 cylinders.. I wanna completely doubt what he says and just assume that he never had the car running with the stock programming, but the fact that my friend that works with him also went to see my car when it was first finished and he says he also saw the car run with no problem..

 

First the 42lb injectors are way too big for your setup so the motor will most likely always run rich at idle. Stick the stock injectors back in and leave them there or try finding some 30lb SVOs.

Of course this means you will need new programming to take care of the injector changes so get that done. In the meanwhile replace or clean the spark plugs.

Also, ONLY talk with PCMforless.com about your tuning needs. You probably wont find anybody more knowledgeable when it comes to 92-93 LT1s than Alvin at PCMforless.com.

 

So why would it be running rich with 42 lb/hr tuning on stock injectors? I would've figured it would've ran lean if anything, cuz the tuning is set to lean out the injectors. I also have cleaned the plugs (multiple times), which did nothing, cuz the car still backfired and died out... seems to still be flooding the engine even with the new programming and stock injectors (possible explanation for I can't rev the engine, and when I give it gas once the car begins to fire to bring up the revs it just backfired and dies, not to sure though), which is continuously fouling the plugs every 5 secs, not to sure why, almost seems like a timing issue, which would make a lot of sense IF the guy who built the engine hadn't ran the engine and drove the car with the base timing set at where it is.

As for tuning, Ion is in the area (well about 60 miles away) and is doing it. I actually bought a normal adapter and chip from him and am waiting for that, but it doesn't seem that it will neccessarily fix the problem because the switching adapter is reading the programing, possibly not correctly, I dont know, but I have a feeling that this piggyback adapter also won't fix my problem here, and that there is something else that isn't quite right here. Should it run off of 5 cylinders well enough to move the car 15 feet? Even if not, why would this cause the just cleaned plugs to foul out again?

 

any suggestions on a good place to start or an idea of what is going on here?

 

I am not to familiar with how the opti spark distributor works exactly, but if the plug wires are correct, is it possible that the base timing is off on the distributor?

 

Are ya sure the plug wires are on correct? Is the valve adjustment correct?
If the opti is on the engine it doesn't mean it is correct. If the pin was to long then it will tear up the opti. Ya need to check it. Mark the plug wires when ya take it off and check that with the numbers on the opti.

 

Your O2's are probably ruined from running 42 lb/hr injectors on programming that is set up for 24 lb/hr. I would put the stock injectors back in, reset the computer, replace O2's, and replace spark plugs.

 

Nope, O2's are disconnected, and PCM is set to run on open loop. (wish it was that simple though..)

 

The plugs being crossed was the one of the two things that I could think of here, cuz that would for sure cause intake backfiring, I will definetly check that out tommorrow. As for the opti, it is a 93 nonvented opti and runs off the spline on the camshaft not the dowel pin. BUT the other thing I could think of that could be possibly be causing intake backfiring and the car to run like it does for a few secs and die out would be the base timing being off... correct me if i'm wrong but on a normal distributor that would just mean turning the distributor until the timing is correct, does that also work on a opti spark distributor? If so, how does that work, cuz looking at it, it doesn't seem like changing base timing this way is a option...

 

The opti has only one way it's supposed to be installed and is not rotated like traditional distributors to change timing. The PCM changes timing. You'll notice how large the contact area on the rotor is to accomplish that. Many folks have installed the opti incorrectly. Don't understand how but they do it.

Wires crossed should have been the first thing you looked at. If that turns out to be ok then you should check a few basic items.

You can do a check of both valve timing and distributor timing at the same time. Take a valve cover off and pick a cylinder and rotate the engine by hand to get it to top dead. Pay attention to what the valves are doing as the piston moves to confirm the valve timing is at least close.

Once the piston is at TDC, remove the cap from the opti and note the direction the rotor is facing. Now check the location of the contact in the cap for the cylinder you put at TDC. The rotor should be facing the direction of where the contact for the cylinder at TDC is when the cap is in place.

This will allow you check several things at once including the health of the opti internally.