ECU clicks at startup then goes away. ECU, or does some other part cause this?

[SnowBird]

I read its the ECU turning on and off, but someone told me the power transistor can cause it to do this?!?!

Heres what happens, Only at cold startup it will start, stall, start, stall. Then it will finally respond to the gas pedal, sputtering real bad with the ECU clicking away and the check engine light on. It will do this for about 10 seconds and then the light goes off, ECU stops clicking and the car runs normal. This only happens first thing in the morning on the cold start up, but its scary to drive around like this.

Oh, and my ECU doesnt smell, and I took it apart to find it is the cleanest one Ive ever personally seen - you could eat off it, no discoloration anywhere, and no leaks.

 

[rEclipserGST]

Fuel pump maybe? or a bad relay im guessing

 

[Aphix]

Check your battery connection it is probably loose somewhere. That'll cause it.

 

[Fiascoxl]

my guess would be the MPI relay., its right there by the ECU so you would think that its "clicking" instead.

 

[SnowBird]

Thanks for the input, my battery connection is good and has new terminals. Next time it starts Ill just dig around to see what is clicking.

But would a relay really only click at start up?

 

[delta448]

The clicking is a relay throwing in/out. If it sounds like the ECU area, it's probably either the fuel pump relay or the MPI relay, as those are the 2 large relays in that area. If you pull the stereo out or remove the passenger side center console trim you can look into where they sit, check the resistance to ground first with a ohmmeter/multimeter, and do not touch the high current side of them while cranking or running the engine.

 

[SnowBird]

The clicking is a relay throwing in/out. If it sounds like the ECU area, it's probably either the fuel pump relay or the MPI relay, as those are the 2 large relays in that area. If you pull the stereo out or remove the passenger side center console trim you can look into where they sit, check the resistance to ground first with a ohmmeter/multimeter, and do not touch the high current side of them while cranking or running the engine.

Thanks

Ill have to tear it apart and check it out again. Its definetly coming from the ECU area, but only clicks when the check engine light is on at startup. I just dont understand why it would give me hell at startup for 30 seconds and then let me drive the car the rest of the day with no problem. I thought when relays went out they went out without warning and that was it. So...where the hell would I get these relays? They dont sound like something NAPA would stock.

 

[delta448]

^ That sounds more like a battery issue. What kind of shape are the main battery grounds/grounding cables in?

 

[SnowBird]

^ That sounds more like a battery issue. What kind of shape are the main battery grounds/grounding cables in?

I replaced the main battery ground cable a week ago. The original post I put up still best describes my problem. As long as the car is running its fine. Let it cool down for a couple hours and it wont start for about 7 attempts, then run like shit with the clicking and engine light, then the light goes away and the clicking stops and its good to go. Killing me, because I kinda suck with a multimeter, but I dont wanna buy an ECU and have it not be the problem.


Heres a new question. Is the clicking a result of the check engine light, or is the check engine light a result of the clicking?

 

[ShawnsGarage]

The clicking you hear is most likeley the MPI or fuel relay. They are located behind the radio on the pass side by the bottom of the ecu. Pull the two screws and pull it out so you can acess it and see if that is whats clicking

 

[SnowBird]

WTF? I went to the junk yard and pulled a MPI relay outta a non-turbo 4g63, plugged it in and it started right up. Then I unplugged the new one and plugged in my old one and it also started right up. This is crazy.

 

[ShawnsGarage]

Inspect the MPI fuse. Make sure there is no burnt look to it. then just wait and see if the problem rises again.

 

[assassin3117]

i would find someone who has an ECU you can swap and use it to check. mine car was having a few more issues than your describing but it would start stall start and stall and i would hear a clicking coming from the MPI relay. i looked at my ecu and it looked great. but i decided to switch the ecu out and it fixed the issue. just find someone close who has one and try it, might save you allot of hassle. let me know if this helps.

 

[delta448]

WTF? I went to the junk yard and pulled a MPI relay outta a non-turbo 4g63, plugged it in and it started right up. Then I unplugged the new one and plugged in my old one and it also started right up. This is crazy.

Sounds like bad connections/bad grounds. Still could be battery related, but likely the relay was just making poor contact on one of the signal side's connections.

 

[SnowBird]

So the ECU totally crapped out today while driving on the highway, it started clicking like crazy causing the car to buck until it wouldnt run anymore. I had my old ECU in my car so I swapped it in real quick. Of course the car started right up but this ECU must be messed up too.

When it was in my old car it would make the car sputter and not want to run until it was warmed up completely, and even if I would start it up after running in a store for 5 minutes I would have to sit and let it idle, or help it idle and let it clear up before I could go anywhere. I always thought it was because my FIAV was blocked off.

Im suspecting this is a problem with the ECU, seeing that with the ECU that just died on me didnt host this problem. Im going to buy a non-eprom one soon.

 

[assassin3117]

PM me i have and old one you can just have. it already has the old caps taken out. just go to radio shack and buy new ones for like 2 or 3 bucks for all of them. not hard at all to solder them in.

 

[delta448]

So the ECU totally crapped out today while driving on the highway, it started clicking like crazy causing the car to buck until it wouldnt run anymore. I had my old ECU in my car so I swapped it in real quick. Of course the car started right up but this ECU must be messed up too.

Open up and look at your old ECU, do any of the capacitors have leakage or look bloated? If the problem is truely the ECU failing, 99% of the time the capacitors going bad are the source of the ECU's problem. The rest of the ECU is composed of solid state electronics and those components possess a lifespan much longer than yours when used under the conditions they were engineered for.

If you have a problem other than the ECU and switching the ECU fixed it, it's probably going to be temporary and you're just going to fry that ECU as well. Take care of the problem that caused your ECU to go bad.

When it was in my old car it would make the car sputter and not want to run until it was warmed up completely, and even if I would start it up after running in a store for 5 minutes I would have to sit and let it idle, or help it idle and let it clear up before I could go anywhere. I always thought it was because my FIAV was blocked off.

You should investigate this further, your entire problem may be closely related to this issue. I'm not sure I can help further there, but there are several members here who possibly could.

Im suspecting this is a problem with the ECU, seeing that with the ECU that just died on me didnt host this problem. Im going to buy a non-eprom one soon.

Just do yourself a favor and inspect the ECUs you already have first. Replacing capacitors is not a huge deal. If you aren't comfortable with it, any electronics or computer repair store should be able to do it for you; for way cheaper than the cost of buying another ECU.

 

[SnowBird]

PM me i have and old one you can just have. it already has the old caps taken out. just go to radio shack and buy new ones for like 2 or 3 bucks for all of them. not hard at all to solder them in.

Thanks, I appreciate it, but I need a 90 and I already have 2 ECU's I can play with.


DELTA448 - I also appreciate your patience and all your replies. The first ECU I had that died and was clicking looked spotless inside around all the capacitors, front and back of the board. My old one, the one that the car starts with, does have discoloration all around the caps and such, so I was guessing thats why I have the sputter problem at startup. I know this board is eventually gonna die from the corrosion so Im using it as a temp.

The only reason I wasnt gonna fix the caps is because the first ECU that clicked and died looks amazing, so I cant confirm it is the caps. The temp one thats keeping me alive has enough corrosion that I am worried something else ruined from the leakage. I found one locally for $100 from a reputable guy, hes gonna let me plug and play before I buy it.

The thing that scares me is you said something could be burning up my ECUs? What kind of problem would do that? Thanks again.

 

[cbrfrenzie]

Thanks, I appreciate it, but I need a 90 and I already have 2 ECU's I can play with.


DELTA448 - I also appreciate your patience and all your replies. The first ECU I had that died and was clicking looked spotless inside around all the capacitors, front and back of the board. My old one, the one that the car starts with, does have discoloration all around the caps and such, so I was guessing thats why I have the sputter problem at startup. I know this board is eventually gonna die from the corrosion so Im using it as a temp.

The only reason I wasnt gonna fix the caps is because the first ECU that clicked and died looks amazing, so I cant confirm it is the caps. The temp one thats keeping me alive has enough corrosion that I am worried something else ruined from the leakage. I found one locally for $100 from a reputable guy, hes gonna let me plug and play before I buy it.

The thing that scares me is you said something could be burning up my ECUs? What kind of problem would do that? Thanks again.

Bad Ground connections could cause the ECU to burn up other things, as the High current paths of the Injector drivers could be tring to ground through a component that can not handle that amount of current. You could locate the injector drivers and measure the resitance between the ground pin and chassis ground. If you get resistance there (Greater then 10ish Ohms) , you have a bad ground connections from the ECU to the chassis.

Also, if you have an ECU with really bad corrosion damange, I'll take it off your hands for cheap. PM me if you're interested.

 

[msgg200]

Hi
I have a 91 TSI and I also hear it click before it starts. I have also noticed that now when I turn the Wipers on with the radio on, the radio will shut off and the clock will reset to a different time. Has anyone experience this? Dose anyone know what this maybe. I was told it was the starter but I dont understand why that would cause the problems with the radio when the Wipers are on.

If anyone can help please reply!

 

[SnowBird]

Hi
I have a 91 TSI and I also hear it click before it starts. I have also noticed that now when I turn the Wipers on with the radio on, the radio will shut off and the clock will reset to a different time. Has anyone experience this? Dose anyone know what this maybe. I was told it was the starter but I dont understand why that would cause the problems with the radio when the Wipers are on.

If anyone can help please reply!

different ECU cured my problem, I just bought 2 good used ones for $150. Your problem doesnt sound good, from what Ive read and expierienced is when an ECU starts to go bad all sorts of unamaginable things can happen.

 

[msgg200]

SNOWBIRD,

Where did you purchase your ECU's from? At 150$ that is a steal when, they are at least $1000 or so from the dealer.

 

[resilva]

Your best bet is to send it to steve here on this board. He does top notch work at very reasonable prices.

I don't see the point in buying a used ECU that can go at anytime when you can get yours repaired to as good as new for the same price or less as a used one.

I recently sent my 1G ECU to Steve who replaced all my caps, fixed the damage traces on the board that the leaking caps had burned through and even socketed my ECU since it's a EPROM ECU.

He charged me $135 to repair and socket my ECU, the quality of the work is of the highest quality; extremely professionally done. My ECU is as good as new.

I don't think people on this board realize Steve does amazing ECU repair work.

Here's a link to his site http://simon.chi.il.us/ECU


-Richard Silva-
'93 Talon TSi
O.G. Socal Club DSM

SNOWBIRD,

Where did you purchase your ECU's from? At 150$ that is a steal when, they are at least $1000 or so from the dealer.