Having issues with this 92 pickup (still). The issue, It's idling rough, it seems to drive decently on my 30mile commute. I had a big fiasco a few months ago, I let the battery die and it would not run right to save it's life. I ended up replacing distributer, TPS, plugs, wires, igniter, and ECM. turns out, mine actually had a bad ECM, that had been correcting for a bad distributer for a while, best I can figure. when the ecm reset with a new battery, it would not run. I've got it running fairly decently now, after replacing knock sensor and sealing up all the vac leaks under the manifold. It's still got a rough idle, and I had to notch the distributer to get it to 10deg. It's maxed out plus some counter clockwise. I thought the distributer was a tooth off, but I've tried that and cant get it to idle. the old distributer was right in the middle, I was running it at 12deg adv. I noticed that the timing belt seemed to be loose when I did the knock sensor, but it didn't lightbulb my brain until now. could a loose belt cause these issues? When I did the knock sensor I set the crank to tdc, the cam gears lined up exactly where they should, so I didn't think much about it. I plan on fixing this and another issue I noticed (pcv grommet is torn, pcv hose is kinked. didn't have parts to fix) this weekend. I am hoping, as long as the gears and crank still line up that I can loosen the timing tensioner and fix that. The timing belt is about a year old. (I used the aisin kit from rock auto). Side note. I have been getting code 26 (rich condition) every couple hundred miles. I reset the ecm and continue on. I replaced the injectors with flamethrowers (4hole), and denso O2 sensor. truck has no cat, and turbo muffler. I'm hoping someone has an idea I haven't thought of, I've been reading posts for 2 weeks now trying to come up with more.

 

I'm going to adjust the tensioner tomorrow, install new pcv hose and grommet, and check plugs/wires/etc, I'm hoping once I get the belt tight the distributer is 1 tooth off and I can get the timing correct. Anyone got any other ideas to check? engine is EGR / pair deleted, pulling the plenum takes 5 minutes. I've got new plenum and throttle body gaskets although the ones on there are only a couple months old, just don't want to leave it to chance. Should I change the O2 again? it's got a denso replacement I put in there 3 or 4 years ago. VAFM is still original and was opened when I pulled the connector out and had to re-solder a couple spots. I adjusted the spring tension in there a couple times, back and forth, never noticed any difference, so it's back where it began.