Author Topic: Running Rough (Read 949 times)

flyingbrick · « **on:** Oct 09, 2003, 01:24:49 am »

I've been having a lot of problems with my car since I rebuilt the motor. Now that I think about it, Iwas having this problem before. The car starts to miss when you try to hold a rpm around 2200 as long as you are not under a load. I have checked and rechecked my vacuum routing, ignition timing, timing advance, feul pressure, plug and distributor air gap, vacuum leaks, and have changed my injectors. I'm getting this feeling that maybe my air flow meter is bad. I've got a A1-CARDONE rebuilt unit in it right now because my fatger took the one out of my celica to put into his 4-runner while the car was sitting in the garage for years. The reason I think it's bad is because I can only get the idle up to about 900 rpm's when adjusting it at the throttle body. I pulled the hose from the idle air control motor off to see if it was working and the car stalled right out. It's my guess that the IAC is working fine. The other thing is that the cars smells like it's running really rich. The way I figure it is that if the car won't idle any higher, maybe it's getting too much fuel (like I said it smells really rich) I've got perfect fuel pressure, it's not too high. I think that the air flow meter is telling the processor that the door is open further than it actually is and causing the mixture to become richer than it needs to be. Any ideas?

wadadlianu · « **Reply #1 on:** Oct 09, 2003, 01:30:18 am »

Check your TPS voltage and your AFM also. I cannot remember the correct voltage at idle but throttle wide open should be 5volts

flyingbrick · « **Reply #2 on:** Oct 09, 2003, 01:40:35 am »

I'm going to check the afm tomorrow, but I'm not sure what to do about the tps. I'ts really easy to set the thing, but when you go to check it's operation they say you have to "make" a tool. They want you to make a gauge of sorts 45mm tall with a, and don't hold me to these numbers,45* angle on one side and a 30* angle on the other side and put it into the throtthe body and check voltage when the throttle blade is at these 2 angles. There is no mention of being able to buy one of these tools in the factory service manual, you know, no sst number. I don't have a problem with making the tool it self but I'm confused about what kind of material to use. Maybe really thick sheet metal?

wadadlianu · « **Reply #3 on:** Oct 09, 2003, 01:47:16 am »

maybe you could use a coat hanger and fashion it into an L with the correct angles. Then all you would have to do is cut it to length

flyingbrick · « **Reply #4 on:** Oct 09, 2003, 01:53:34 am »

Sound's worth trying. Thanks man!

Film · « **Reply #5 on:** Oct 09, 2003, 04:11:54 am »

You might want to check the cold start injector. If you are sure the car is running rich and the ignition system is OK, this injector may be leaking fuel. It is dedicated to cold start function only and should normally be off during normal engine operation.

If this system looks vaguely familiar, it's 100% Bosch L-Jetronic* or a licensed Toyota hack of Bosch L-Jetronic. BMW used L-Jet in some of their cars about the same time.

This bit of info might help you find some useful non-Toyota L-Jet troubleshooting guides.

Also, check your coil condition and coil polarity. This assumes you can reverse coil polarity on these cars (probably not).

Maybe the regular injectors are bad. You did say it sat for an extended period.

* Bosch LH-Jet is similar but uses a significantly different (and better) method of measuring the incoming air.

flyingbrick · « **Reply #6 on:** Oct 10, 2003, 12:30:23 am »

I already changed the injectors. I guess I should check out my coil.

Teranfirbt · « **Reply #7 on:** Oct 10, 2003, 03:28:15 am »

Check the cold start injector. there is a fuel line that runs to an injector on the side of the upper intake plenum.

flyingbrick · « **Reply #8 on:** Oct 13, 2003, 01:47:48 am »

how should I go about checking the cold start injector. Should I just pull it out of the manifold and run the car. Actually I guess I could take it off the car and just hook up fuel to it without it getting any power.