Will not run if it is or has been raining

WannaBREz · Post by **WannaBREz** » Fri Jun 26, 2009 7:27 am

I am having a problem. If it is raining or had rained during the day, my car will start like its fine, and then the blinking lights on the ECU just stop and it will not idle, becomes really hard to rev, and has a strong gas smell. If I let it die, it will not restart. Now if I let it sit for a hour or so, it will fire up like nothing was wrong.

Is moisture from the humidity getting into the ECU? Can I put a layer of hot glue or something on some part of the circuitry to keep it from doing this?

Matt · Post by **Matt** » Fri Jun 26, 2009 6:42 pm

i've had this issue with another user who had rain getting into his Z31 down inside the front guard and then into the ECU

it may be pooling and shorting out circuitry. you need to fix the cause of the problem before it causes any damage

WannaBREz · Post by **WannaBREz** » Sat Jun 27, 2009 6:11 am

Its not getting into the car. The ECU is on the drvers side kick panel, I would know if it was leaking in. This can happen if the car is in the garage also while its raining or had been.

skylinegtrhr · Post by **skylinegtrhr** » Sun Jun 28, 2009 3:59 am

What Nissan You have?

Matt · Post by **Matt** » Sun Jun 28, 2009 10:43 pm

i would be likely to think that there is some other connectivity issue then affected by these factors. I've only had once incidence previously which sounded similar (and wasnt water getting in the ECU) and ended up being a connector crimp problem with one of our very first connectors

when the problem is occuring, remove the top cover and then whilst ECU is running limp mode
http://www.nistune.com/docs/Installatio ... ostics.pdf

wiggle the wires from CPU connector to the board and push down on the board and see if it makes any difference to the operation of the ECU

let us know your vehicle type also

WannaBREz · Post by **WannaBREz** » Tue Jun 30, 2009 8:19 am

I will try what you have stated above. Supposed to rain all week, so it will be a good test period. As for the kind of Nissan I have. Its a 1973 Datsun 240. It have a 1981 280zxt FI and ignition harness modded to run the z31 ECCS and MAF. I now am running a z32 MAF with the Nistune. Only thing stock on the car is the shell.

skylinegtrhr · Post by **skylinegtrhr** » Wed Jul 01, 2009 12:21 am

Did You check gasket on distributor cap? is there any moisture in it when this problem happened ?
If this problem is moisture induced in first place as Matt wrote...

WannaBREz · Post by **WannaBREz** » Thu Jul 02, 2009 5:19 am

Can I use electrical grease in the plugs to keep the connections good and moisture out if there is moisture getting in?

Matt · Post by **Matt** » Thu Jul 02, 2009 4:55 pm

you can try it but shouldnt make much difference to the board?

WannaBREz · Post by **WannaBREz** » Fri Jul 03, 2009 8:41 am

I took it all apart today to inspect it. turned the key and moved wires and wiggled plugs making no difference. Everything is working fine. Started right up. So I will have to wait till it messes up again to fiddle with things.