Injector problems...I think

[THAWA]

I was driving home today and as I was nearing my house I felt the car die, then restart, in less than half a second. I thought to myself, hmm the only codes I've been throwing are knock sensor, and iac valve this couldn't be either of those could it? So I drove around for a bit more, and was idling at astop light for a couple of minutes. when I felt the car try to die, and then the rpms surged (probably the iac valve opening) and stayed there for a while. and slowly went back to normal idle. I thought to myself, this has to be this stupid IAC valve, hmm, but why would it all of a sudden happen? So I stopped at home and pulled the codes. I got 24, 11, 12 (not 22 hurray!). Now I'm not all THAT worried about 11, as damn near anytime the car has died (from maf problems, to iac valve problems, to spark plugs, to plug wires, cam sensor, etc) code 11 has been thrown. But code 12 is new, I've never had injector 2 fail, or throw a code, so I do believe there is somthing up with them. Could this be from my using a 92 ECU with my stock 4eat 90 injectors? Or is this pretty much bad injectors. Also lemme note that as I've been driving a lot lately, I've been feeling the car sort of holding back. When we were up in the mountains I chalked it up to the elevation, but now I'm starting to think this injector is actually bad. Also I've got magnecores, and the plugs are barely 6 months old. Fuel filter is bout 8 months old, air filter is 6 days old. I guess I can drop the cash on a good laptop and finish this scan tool or something.

[BAC5.2]

Didn't the 92 MT's have different injectors than the 90 Auto's? Might, indeed, be your problem.

My IAC would randomly kill the car. Idle fine sometimes, kill it others.

[free5ty1e]

by the way, you dont need a good laptop for the scan tool. Go find a used computer store and get the cheapest one they've got, it'll work. Guarantee. I'm running it on an old 100MHz P.O.S. with 8MB RAM and 800MB hard drive, and its overkill. Gotta love DOS.

[vrg3]

I dunno... the symptoms sound a little like a vacuum leak to me... 'course, since I had a vacuum leak problem I tend to see them everywhere. Still, it couldn't hurt to try the starting fluid check.

I have gotten spurious injector codes before. I cleared them and they didn't show up predictably again.

The injectors were indeed different, at least in shape. They're both pintle-type, though, so the internal construction may be similar.

I don't think using the "wrong" injectors could upset the ECU. Its monitor circuitry is probably looking for a big voltage spike when the injector closes, and it gets upset when it doesn't see it or sees it at the wrong time. Any solenoid valve of the approximately correct impedance should produce this just fine. It's plausible to me that EM interference could occasionally cause the trouble code. I dunno.

Maybe try running some Sea Foam through the gas tank, just to see if it makes any difference? Also, make sure the injector clips are firmly connected to to the injectors... Unplug them, make sure there's no grease or dirt in the contacts, smear in some dielectric grease, and reconnect them, making sure they click.

And you should definitely try clearing these codes to see which ones come back.

[THAWA]

by goo dlaptop, I meant one that has a working parallel port, or a battery

Well, I'm almost certain there's a problem with something. about 80% of the time that i'm in 3rd gear and slowing down, braking or not, a code is thrown and when I come to a stop the car dies. Everytime it happens it happens between 2500 and 3000 rpms. It's like clock work. I'll try the starting fluid stuff, and anotehr can of sea foam.

[vrg3]

Wait a minute.

Codes 24, 11, and 12?

24 is for the IAC valve.
11 is for the crank angle sensor.
12 is for the starter switch.

Is there a typo somewhere?

[free5ty1e]

No battery on my laptop... even if it were good its charging circuitry is completely fried. I've got a voltage kicker circuit hooked up to 12V to boost it to the 16V I need to run the laptop, and a nice connector I soldered on. Ghetto-rigging at its best. But I digress. Back to the topic, to which I have absolutely nothing useful to add

[Legacy777]

I'll add my little bit about the injectors. I doubt you'll throw a code for them.......I will say that I do think my car is running richer then it did with my original injectors. It's possible that the pulse on the 92-94 injectors is less to get the same fuel. So you may be seeing less fuel to the engine....however the O2 should help correct that.

If you have a laptop and can run the scan tool prog. Check and see what your alpha correction factor is.

[THAWA]

word, I guess there was a typo, I was thinking 11 was injector 1 and 12 was injector two, but now i remember 14 is 1 and 15 is two. Anyway, this makes sense still as crank sensor failing would cause these kinds of problems. I'll eventually buy a lappy taht works.

[vrg3]

What were the actual trouble codes?

[THAWA]

what I posted above

[vrg3]

Oh. Okay. An IAC issue could cause this, right? And so could a crank angle sensor...

If you get the crank angle code every time your engine stalls, you might have a weak sensor. Generally, both the crank and cam angle sensors quit outputting signals at the same time, but if one is weaker than the other it could cause the signals to die at different times in a stall. You might want to grab a crank angle sensor from a car in the junkyard and see what happens when you install it.