computer problem?

[kevin keener]

here it is I had a short in my o2 sensor wire it popped my 20amp fuse for the mpi. While I was troubleshootimg my car I found that the capacitors had leaked onto the board only a little. I had a friend who is very familiar with soldering coponents onto boards replace my capacitors and cleaned the little damage the capacitors had done. Replaced the 02 and hooked the ecu back up and the car will not start, turns over. I can hear the fuel pump going. The check engine light does go off after 5 seconds and boost guage goes to 0. My question here is there another way you can tell if ecu is bad?Or do I need to start somewhere else, any help would be appreciated.

 

[tunethis]

It would be nice if you had a known "good" ecu to test. I had an ecu that had leaking capacitors and would not start the car. It passed the gauge test too. The ecu wasn't grounding the injectors so, the engine wasn't getting any fuel. The car did try to start with starter fluid so that's how I figured that out.

Is your ecu bolted to the car? If not, it won't start.

 

[kevin keener]

No the ecu is not bolted to the car right now,but after troubleshooting it for awhile the though did occur to me so grounded it with a jumper wire, so that should work right. I tried it after I grounded it but still would not start.Anyway I was also wondering if maybe I bunt a ground up on a sensor or something, but I have checked all sensors on the harness side for grounds and they have one.

 

[kevin keener]

how did you check the injectors for ground?

 

[tunethis]

Try bolting it up with all 3 bolts. Maybe the ground wire wasn't enough? It took me awhile to find my issue because I bought the car running, let it sit for a month and came back to the car not starting. I had no idea what was up. Eventually, I tried starting it by spraying a small amount of starting fluid into the TB. It tried to run after I sprayed the fluid in the intake. I instantly knew the injectors were the problem. I knew they worked but, I didn't know what was causing my problem. I hooked up a ground wire to one of my injectors and when I cranked the car, fuel squirted out. At that point, I narrowed it down to the ecu. I eventually got another ecu and the car start up immediately after I installed it.

That may not be the issue for you but, first bolt the ecu up then, try starting the car with a little starting fluid in your intake. If it tries to start, you have issues with your injectors not firing. If it still doesn't start, you have other issues. Also check for spark. It may very well be the ecu not working correctly.

Do a search for "no start" to get more trouble shooting ideas.

 

[kevin keener]

it just started, and ran for 1 minute and then died. I had the isc and maf unplugged. I tried to restart it but to no evail. I got the negative unplugged right now to erase code, then going to plug back in the maf, and keep isc unplugged , to see if it runs, if not then vice versa. any clues, please share.

 

[snowborder714]

Have you checked out the sensor ground?
blownsensorground [ECMTuning - wiki]

 

[talondave]

You dont have to have the ecu bolted up to run your car!! Mine is on the floor as we sweak and runs fine!!

 

[kevin keener]

I have the ecu in my hands, and I still cannot find any of those grounds.

 

[snowborder714]

For a 1G ECU, the symptoms are the same, but the burned track can be on the top of the board connecting to ECU pin 24 or on the bottom of the board in the are beneath IC101.

Look for that. If you're not sure where pin 24 is, here is a pinout.
ecuwiringinformation [ECMTuning - wiki]

 

[tunethis]

You dont have to have the ecu bolted up to run your car!! Mine is on the floor as we sweak and runs fine!!

I guess my car is weird because I bought an ecu, plugged it in and left it on the floor and the car wouldn't start. As soon as I bolted it in, the car started right up. That's why I mentioned it.

 

[kevin keener]

pin 24 is grounded, so I guess the sensor ground must be good. I put the ecu back together and charged the battery now runs sluggish and showing on my logger that the knock sensor malfunction. I checked the manual and harness is good meaning on one pin is grounded and the other has 8 volts. I hooked another knock sensor up to it and the same. Is it time to send the ecu to get it checked out or what, or is their another way I can make sure that the ecu is bad.

 

[bnr32_coupe]

I have the ecu in my hands, and I still cannot find any of those grounds.

that's really unusual... i suggest picking up a new ECU. who knows what else is messed on that one..
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[kevin keener]

I was thinking of sending to get repaired. I just wanted to cover all my bases. I did not know if there was something I was missing or another way of going about finding the problem. I have already looked everywere around here for a ecu but could not find one.

 

[kevin keener]

update, finally got around to it and sent my computer to steve. It came back plugged it in runs like a champ.

 

[GooeyGus]

Sweet!

Steve to the rescue!!

That sure is weird that the CEL came on and went off like it should and the car still wouldn't start...

 

[kevin keener]

Yah, I didn't understand it either. I'm glad it's finally repaired.

 

[project98dsm]

I don't mean to jump threads, but I posted in another one about an ECU issue. I came back from 3 weeks in the field doing training to a car that started right up and I let it idle for about 5 minutes or so. Came back a couple of days later and it just sat there turning over. Fuel and spark is there, just not getting fuel past my injectors. Pulled my ecu and noticed some cap leakage. I'm just praying this IS in fact my problem, but I really won't know anything until I get my eprom in which will be another week or so...I don't really have a lot of time to work on my cars being in the Army and all. I guess we'll see but I'm glad you have you're issue worked out and all is well, hopefully mine will be too haha.

 

[project98dsm]

Well, I got my ECU in from Jeff at dsmchips and installed it, car started right up. Good luck with your issue and keep us posted on everything.