Ok so here is the story, Yesterday we had a local get together where we were going to Hooters. I just got my car all shiney and detailed so I jump in and start it up (Like always) and I start heading down the street. The usual cam surge was happening so I thought nothing of it. I get about 2 blocks away and my car starts bucking like an angry bull. I cranked the wheel to the left and pulled into my buddies driveway. I remembered that I had found a small manifold vacuum leak, so I thought maybe if I repaired that leak it would fix my problem. Well... the car stalled when I pulled in so I started it 2x more but it fired and died right away. Then I waited a minute while I talked over grabbing a piece of vacuum hose with my buddy and I started it...it fired and idled as nicely as it could considering the mods and the presence of a stock chip.

I headed out to hooters and drove there and back successfully until I reached my street. I started coming down my street and all the sudden the car started bucking again. I went through everything under the hood I coluld think of today. I cranked the fuel pressure down a bit as I thought it was running too rich (Black smoke while revving it) I checked the plugs, they had a little bit of carbon deposits on them. Checked for more vacuum leaks... all in all it seemed that it should be in good working order. I even checked that all the plugs were snug, had the plug boots firmly on, and that the header bolts were all tight.

To no avail did any of this help. I can start the car but only keep it at a civilized idle if I apply gas to bring it to 1000 RPM. I placed my hand on the fuel lines on the drivers side of the car that come from the tank and hook to the fuel rails. I felt a ticking like you would if you were to touch an injector while the car is running. The ticking increased with RPM.

Anyone have any ideas as to why my car all the sudden decided that today was the day it wanted to be cranky?

A few things I don't think that I mention in my sig that are important are: Plugs are 2 heat ranges colder than a stock plug to compensate for the compression. The Distributor is set at between 6-8* advanced, although it could have moved and maybe thats the problem??, um... replaced factory fuel pump with an AirTex pump that I grabbed at work. Its supposed to be a factory replacement. Coult it have a short circuit in the fuel pump??

Anyone with any guesses, I'll try to check everything suggested. Thanks in advance.

 

Check your timing with a light, and your fuel pressure with a fuel pressure gauge. Also get a custom prom

 

Those are the top things on my list. On the other hand I have just begun to burn custom proms. The "stock" bin I was using at the time was the ARAP.bin. You know what I am talking about. It ran absolutely fine for a few days then Crapped out on me.


I'll check those today.

 

It's an 89, with TPI? Is it still MAF as well? If so, sounds like the MAF sensor is dead.
Try disconnecting the MAF and see if it runs better. The SES light will come on eventually, and the car should go into limp mode.
If it actually starts to idle and stops bucking when you accelerate, that is more than likely your problem...

 

BTW! I just took a look at the .bin file I had been using. Its supposed to be the ARAP.bin. Tell me if this looks strange at all!??! I am looking at this bin file and the tables look awfully weird. Its almost as if the .bin is screwing up my WINBIN editor. The 3D spark advance table is messed up. Actually all of the 3D tables are messed up, I get 32, 4, 8, 64, (blank), 80,9,6 across the top. This never happened before. In the flags section I only get 2 choices of fields to change instead of the normal what is it 4 or 5?

 

LeeH, I tried unplugging the MAF and it still idled poorely. I get an immediate SES code but still no smoother idle. I am leaning toward a possible fuel delivery problem. Not sure.

 

After lots of playing I found that my TPS was to blame. I could pull the throttle open under the hood about 1/2" and I would get no response from the engine for a few seconds. ( About 5 seconds) Then the motor would start to rev up. I just replaced the TPS and set it to exactly .54 volts and it works much better. I still need to set the IAC now though.