Progress Thread Matt's 93 Lx - Running Issues

Thanks for all the tips. It fired right up with the new coil. Set the idle, reset the computer and went for a ride. Runs much better than before but still not perfect. I swapped in a new distributor to see if that would fix anything, but didn't change anything. No codes still. The one thing I'm really questioning is if you bleed the fuel rail from the schrader, a little bit of fuel comes out and the pressure is at zero. I remember a while ago when I was installing the gauge (when the car ran great) it took a decent amount of time and fuel to bleed it down to zero. It will hold pressure for a few hours though. The adjustable FPR is getting pretty old. The car definitely seems lean up top, but I dont have an afr gauge. Thoughts?
 
I set it to 39-40 with vac off, plugged vac in and dropped to about 30. It's still around there. I need to try and borrow a gauge that I can see while driving and see if it drops.
 
I rescanned the car the other day and came up with a MAF code. Swapped the MAF with my stock one (had sn SN95 on there) and the driveability was way better. The stalling when coming down to idle was still there though. Yesterday, i dropped the idle to about 700, got the TPS to about .65 (I couldnt get it any closer) and did an idle reset. Much better all around. Still stalled sometimes though. I picked up a new Motorcraft TPS since my other one was an old aftermarket unit, and I cleaned the EGR. Got it set to .85 and did an idle reset. Now it's stalling pretty much every time it comes back down to idle, but I'm not sure its related to the TPS swap.. No KOEO codes. I did the running codes and got an 18. Ran out of time to look into that, but the spout is in, and all my grounds "should" be clean. Would the stalling be caused by the 18? I'll have to try another TFI. I also checked the O2 heaters to make sure they were getting voltage - all good.

Getting closer...slowly.
 
IAC is good. It adjusts the idle when plugged in and i cleaned it anyway. Moves freely. Next time I get some time I have to look into the spout code - trace the wires back to the ECU etc. Can I unplug spout and set my base timing to ~28 for now? Will that help the idling?
 
Running Code 18 is SPOUT grounded, so i'm not getting the computer advance. That's why i was thinking setting the base timing higher for now until I get the 18 resolved. Not to drive around all the time, just to get it back and forth to the shop.
 
After tracing a bunch of wires from ecm to coil, spout, etc, I checked the ECM and I have one burnt cap and another leaking one. I ordered some caps to attempt the repair. If it doesn't work out I'll have to get a reman. I'm really hoping this fixes the code 18 though
 
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I hope it works. These computers are getting old.

Post some pics of the repair process.... I'm sure itll help folks in the future.
 
I had to replace 2 caps in my old computer that went bad. It wasn't that bad of a process. A recommendation is to use a straw for desoldering the old caps. Put the soldering iron on the old solder tonremelt it and blow through the straw to force the olds solderout.
 
I had to replace 2 caps in my old computer that went bad. It wasn't that bad of a process. A recommendation is to use a straw for desoldering the old caps. Put the soldering iron on the old solder tonremelt it and blow through the straw to force the olds solderout.
Did it work?
I like snorting through the straw myself:eek:
 
ok so it sort of worked! For the solder removal I picked up some solder braid, which was very helpful. Just lay it over the hole once the cap was out and touch the iron into it and it sucked the solder right out. One of the caps was completely detached, the second was barely hanging on, and the third was mint. Replaced all three. Car definitely runs better in the mid (it was lean before) but I'm still getting that stupid KOER code 18 and it likes to almost die when returning to idle. Along with new code 8 (???) and code 12. I'll try a new IAC for code 12, but it idles up when it's cold and when the KOER test is going on so I'm not sure if that will do anything. There was one more code that I can't remember but I had to shut the car down for the night since I could feel my neighbors hating me.

More progress Saturday, hopefully.
 
Some pics of the process.
 

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