abumchuck

I was out of the country for six months and my car sat in a garage for pretty much the whole time other than one drive around the block a few weeks in and a 20+ mile drive six weeks in. So it sat without moving for 4.5 months. It sat on a trickle charger with a quarter tank of fuel. When I got back about a week ago I plugged in my block heater for a few hours and it started no problem. I figured after sitting for so long it might like starting with a warm engine. I filled the tank with 92 after a few miles of driving. The engine seems okay (not great) driving around but the car won't start anymore without preheating the coolant. It's been about 40* the four/five times I've tried it. I can crank it forever and it won't fire. Well, on the first try sometimes one cylinder fires one time but then nothing. Last winter the car cold started in 30* weather. Sometimes it struggled a bit but not too much. I'm also now getting a bad sound at idle. The car never idled great (AEM EMS) and sometimes drops a little lower than it should. Now when I'm idling and the revs drop a bit there's a terrible rattling noise coming from the engine bay and the whole car shakes a bit.

Just before I left the country I blew out the valve cover seal at the track because my valve cover doesn't have enough venting. I was down about a quart and a half of oil after making it into the pit. But the engine still seemed to be fine (I think I lost most of the oil crawling along the access road back to the pit and not at WOT on the track). After that I hobbled home and parked it.

Are my problems just due to some bad gas that has to work its way through the system (or be siphoned out)? Or do these sound like symptoms of something much worse?

Relevant modifications:

Vortech Supercharger
AEM EMS
RC fuel injectors
Fuel pump on separate switchable circuit


Thanks!

CKit

It's likely your AEM EMS tune. It's not "smart" like an OEM EMS and many people with AEM need a summer and a winter cold start map (especially if the temps swing from season to season). Basically, the EMS needs more fuel than it's getting when the air is denser (cold). You can sometimes get around this by: turning the key to "on" and waiting 15 seconds before pushing the "start" button, pushing down the gas pedal 1/2 way when you're starting the car.

This is one of the reasons I don't daily my AEM EMS car. Also, never store your car without a full tank of gas. Moisture and condensation form in the tank.

rob-2

I agree.

This if warming the block solves the problem it's most likely the map.

abumchuck

Thanks for the input. Looks like I'll have to get new map. AEM doesnt use a separate fuel map for starting?

Any idea why it's so much worse after sitting for awhile?

CKit

There is a different map for starting, but it doesn't correct for ambient temps.

You might want to check your plugs and injectors. Copper plugs that you use in boosted applications can wear after 5-10k miles and could explain the difference from last year if you haven't changed them recently (don't forget to gap properly). Injectors can also stick and rust if left unattended for a while. This is especially common if you use very large injectors and E85.

abumchuck

The plugs have less than 1k miles on them so they should be fine. I'll check out the injectors and run an injector/fuel system cleaner next time I fill up. I guess it's a good excuse to switch to Bosch EV14s.