EMS-4 car warms up then shuts off
 

Hi everyone. My car is at a local shop getting tuned but we ran into a problem. The car fires up right away good idle and good throttle response. But for some reason when it warms up to operating temp it just dies. There is good fuel pressure and the idle screws on the TB have been adjusted all the way. My tuner said he has gone through the idle maps/options but can't make it go away. He is a competent aem tuner and knows what he's doing. He seems to think it's the box itself that is faulty. Anyone here have any other ideas before I send the box back to get checked? Here are my mods:

13B-RE engine
FFE 36-2 crank trigger
850cc primaries/1600cc secondaries
Water/air temp sensors are AEM
Aftermarket speed sensor on tranny
AEM smart coils
Walbro 485 pump
Lots of other things I'm forgetting.

Thanks for any input.

Can you post your map or email it to me? A datalog of all the pertinent parameters when the engine shuts down would be a good idea too.

not sure about the ems but something to check for is the injector settings may be in saturated form but used with peak hold injectors and this causes the ecu to run hot and maybe even shut down to protect itself

I checked out my car today. The problem was not ecu related. I have a small non vented oil catch can setup (one line at the bottom connected at the crank case and a vacuum line at the top with a one way valve so it only sees vacuum).

My tuner said the way it's setup when it reaches operating temp, the blow by vapors kill the engine. I'm going to re-route it and build a proper sized catch can.

Thanks for the input.

I am buying a 87 Turbo II. Once it gets to operating temp it dies also. The owner told me it needs a rebuild and that it probably a gasket that is causing this. He doesn't seem to know much about the car though. What do you guys think could be causing this? Is it going to be something fixable or am I going to need to rebuild it. I am getting it for a good price so I am going to buy it either way, I would like to avoid a rebuild if possible. Thanks in advance.

lol Does your car have and AEM EMS-4? If not, you're in the wrong section. But sounds to me like the apex/side seals are going out, probably would be a good idea to check compression. Could also be an electrical issue.

Back to the subject though. I didn't know this thread existed. I have a similar problem w/ my EMS-4 where it'll start up fine the first time I turn the ignition key on, but if I turn the key off then back on, the EMS will sometimes not come on, although eventually it will.

I'm trying to pinpoint exactly what the problem is, going though and checking continuity. But the EMS definitely has good ground and voltage never drops from what the Batt. Voltage Channel Shows/Logs.

It gets even worse after warming the car up or running it for a few minutes. I thought about the possibility of the injector drivers over heating but it never sputters or sounds like it would start to misfire. Also, I have Bosch EV14's, which are 11ohms I believe and some Deatschwerks which I think were 13-14ohms.

I can also stall the engine and it will start up just fine as long as I don't turn the key off and turn off power to the EMS.

I was told by one of the Tech Support Guys at AEM that I should try putting a password back on the Cal and that should fix it. I haven't tried that yet but I may give it a shot next week if I can get some more time to work on it.

Well I found my problem! Looks like the wiring from the EMS-4 Harness I bought was a bit faulty going to the main EMS relay. Also, the relay gets pretty warm, so the plan is to take apart the relay wiring, double check that everything is good, and put it back together with solder at the terminals and good Bosch Relay or something.

This may be an issue for others in the future using the AEM made 96" lead harness, so I figured I post about this instead of just have a thread w/ a dead end.

Did you confirm if that was the problem?

You can say I did confirm it to be the issue. I took apart the connector to the ECU, though I didn't find anything wrong. I simply took off some of the 12v wires and plugged them back in. Haven't had a problem since(been about 2 weeks).

Oh nice. Would you recommend the aem ems4 over the series 1 30-1800?

Depends on what features you are looking to use. Overall I think the EMS-4 is more capable but has limited inputs and outputs. If you're running pre-mix or mechanical OMP and only need a few features (boost control, idle control, rad fan control, EGT analog in, etc.) then it works great.

If not then probably an AEM EMS Series 2 will work best, since it can handle more inputs and outputs. Also I think they now have a Flex Fuel feature, so if you have a ethanol content sensor you can adjust for that on the fly with a Series 2.

I think i will stick to the series 1 for now. Ethanol in Jamaica is very inconsistent