I experienced random rough starts with my EVO and figured it was just the cold weather. Came out the movie theater one night and it decided not to start at all. Long story short this harness was my issue.

http://www.streettunedmotorsports.co...s_mr497597.htm

One of the Pins must have gotten too hot and the gray plastic pigtail melted a little making the pin recede. Hope this helps out.

After replacing the harness it starts very well.

 

Thanks for the input.

I have a double pumper, but I will check continuity of the wiring.

 

Updated items in black:

So summary of things I have replaced/tested:
coolant temp sensor looks ok in evoscan
replaced both cam position sensors
fuel pressure looks ok and bleeds off normally when car is shut off
plugs are new
new COP
new iat sensor
altering tune modulates is slightly but does not resolve issue
new map sensor
injectors cleaned and tested from FIC all good
new tank of e85
fuel relay in engine bay replaced
both fuel pumps in double pumper replaced
fpr replaced
iacv: so I found that this was installed incorrectly. It was rotated one bolt hole to the left. I put it back to normal and adjust ed idle but still do not have a resolution.


Other thoughts:
tps
crank position sensor
wiring/ground issue

 

So I pulled the plugs and as soon as I take off the coil pack, I notice standing water around the spark plug #4.

I got all the water out b4 I removed the plug. The plug well looks pretty nasty from the water in there, but I can clean it out.

What does this suggest? Could water have just gotten under the plug wire when it rained or something or is this a bigger problem like a headgasket? I assume water cant go up through the plug threads and pool up.

Thinking it could also be a leak from the intake manifold somewhere as well? But it doesn't make sense because this is water not coolant. Unless it was coolant until it sat there for a long time and now appears clear?

The car runs strong once its cranked up and does not feel down on power at all.

Oil looks ok from dipstick, but I have not drained it yet.

Also car has never overheated.

Any ideas?

 

Boost leak?

 

Once it starts and is idling poorly, is it idling lean? like 19-21:1?

 

Boost leak test was good.

Yeah it idles rough like is flooded/missing for a few seconds then its normal. Idle seemed fine but was leaner than other sometimes but not much.

I ordered new plugs. Gonna let everything dry out then try it again. No clue where the water came from.

 

Now that I think about it, I just got a new COP and I dont think it seals as well as the oem coil packs.

It did rain the other day and I have the vent under cover off on my car so that may have been when it happened.

So this may not be related at all. But we will see after I get the new plugs in.

 

I was just wondering because my car does a weird warm start thing where it doesn't like to start up right away and will idle really lean for about 15-30sec. I have yet to find the cause LOL.

 

Yeah mine has been doing this for about 2 months now. Happened out of nowhere.

Hopefully new plugs will modulate it.

 

I believe I have a similar issue. Like my car is bipolar.

 

Mine has been doing it for years. I just leave it LOL

 

Yeah I have to fix it. Something is obviously wrong.

Don't like cranking it over 10-15 times b4 it starts then it sounds likes its flooded for a minute or so.

 

Actually, that's different than mine. Mine fires right up, it just runs really lean for about 30sec or so. Usually, it's on warm starts, but it did it on a cold start, yesterday.

 

So did a compression test:

From driver side to passenger:
125
125
100
125

Added oil to top of piston:
145
145
110
130

I am pretty sure this indicates a bad head-gasket since adding oil didnt help that much.

Also theory is that coolant is passing the head-gasket and making the car miss during startup until after it burns it off.

I still need to do a leak down as well.

What do you guys think?