Starts Then Immediately Dies, Sometimes Won't Start At All

[aaaron]

Hi all,

I'm not really expecting a magic answer. Just more or less documenting for others.

History

Car has just over 100k on it. New battery, timing belt, water pump, cam seals, serp. belt, etc.

It's lowered and has tubular control arms but no engine mods.

Car died at a stop light. Then later had trouble starting.

The next day it started fine but wouldn't start later that day (cold) for my wife.

I did some troubleshooting and swapped the fuel pump relay.

Started right up and so I thought I had it licked.

The car ran fine for a couple of weeks and then the problem returned.

I can tell the issue is electrical. Pushing on the accelerator does nothing.

Car will turn over but not start up. The problem comes and goes.

Today I drove the car several times and then out of the blue. It wouldn't start. More precisely it would start but immediately die.

No response from the throttle at any point. I did tons of Google research and decided to pull the battery cable. After doing so the car started without issue.

I'm thinking my next course of action will be to replace the ECU.

[smooth1]

Why can you tell it's electrical?

Have you checked the MAF and IAT? along with the vacuum hoses?

[chambersp86]

Have you checked it with a timing light?

[aaaron]

Well I don't actually know that the problem is electrical. After I pulled the batt. cable the car ran fine for a month with no symptoms. I have not checked the MAF sensor or the IAT. I should probably to that. Currently the car will crank and eventually start but will then sputter and die. On occasion you can romp on the gas pedal and keep it alive, then it's fine until the next time I shut it off.

[smooth1]

Then it could be a fuel pump. You might want to check that. It's in the gas tank. Theres an access panel after you remove the rear seats. I'd check for good pressure there. If you can't that, then I would tkae it in and have a diagnostic done. They can hook into the ODB plug, run the car, and see what's going on to cause it to die. Might be worth the hundred bucks to save a bunch of time doing it this way.

[aaaron]

I originally thought it might be the fuel pump but the intermittent nature of the problem makes me think otherwise. I cleaned the MAF and IAT sensors yesterday but the problem returned today. I'm very close to ordering a new ecu for this sucker, but I can't help but think some faulty sensor is causing the trouble. The wife wants it dropped off at the dealership but I hate to write that blank check.

[silverbullitt]

Have u changed the fuel filter.

[aaaron]

The fuel filter on the IS is a mesh bag type thing (strainer) that never needs changing. I don't think it can clog like a typical filter.

That said I may replace the fuel pump and strainer just for the sake of due diligence.

[aaaron]

Well I swapped the fuel pump and strainer and all was well for a week. Then it wouldn't start again for my wife. After trying, waiting and trying some more to start the vehicle I told her to disconnected the battery. After reconnecting it the car started right up. Next I'll be installing a new set of plugs before I drop this sucker off at the dealership. At this point I'm back to thinking it's the ECU.

[aaaron]

I replaced the spark plugs and the car has been starting consistently for a few days now. I would not be surprised if the problem returns but so far so good. On another note the idle is a bit rough on cold starts after the plug change. Also there was fresh oil on two of the plugs when I removed them. That can't be good.

[Jumpjmc]

Hi,

I have similar problem with my ES. Did you ever find a solution? Was it the Ecu?