So the other day I was started my car up and had a slightly rough idle. After driving for a minute I got a CEL. I pulled the codes and they were P0300, P0302 and P0303. The car seemed to drive just fine other then that rough idle. I started trying to diagnose it. I pulled all the plugs and did a compression test. Plugs looked good as they only have 2000 miles on them and the compression was pretty much perfect as my engine was fully built 2000 miles ago. I got between 205 and 210 across all cylinders(I have 9.0:1 pistons). I swapped the 2nd and 3rd cylinder plugs and coil packs with 1 and 4 to see if the code would change cylinders. I put it all back together, cleared the original codes and started it. It ran with a rough idle again but it was running and I didn't get a code. The idle smoothed out as it warmed up. So a few days later I go to drive it to see if I can get the code to pop up again and it wouldn't start. I have since changed out the coil packs for brand new OEM packs and that made no difference. I've been working a lot haven't had a lot of time to trouble shoot it. The fuel pump does cut on and I can see fuel pressure at the rail on my gauge while the pump is on.

Here's some history of my car. I had InlinePro rebuild the engine. 2.4L sleeved and stroked with 9.0:1 pistons and a stage 1 head rebuild. New oil pump, all new gaskets, new Inlinepro TCT, new plugs. I have a Walbro 255 pump, AEM rail and FPR. Running OEM ecu (have AEM Wideband everything was running great A/F wise). All of this has 2000 miles on it and it all ran amazing until this issue popped up. Everything else just about has 140k miles on it. The engine wasn't making any weird noises or anything last time it ran. I'm hoping someone can help me figure this out. Any help at all is greatly appreciated. I was getting ready to get all of my turbo stuff and ran into this. Thanks guys.

 

Valve lash (clearance) are set to (exhaust & intake)?


Thanks!

 

I haven't checked. I know Inlinepro did that and like I said it only has 2000 miles on it since the rebuild. I'll still try to check it.

 

I know you have good compression. But, should measure free play --- just to rule out if they are too tight.

 

Yeah it's worth checking. You think that would keep it from starting?

 

Dunno. But, if you did the compression test, when the engine was at operating temp --- may not reflect compression when engine is cold.

Measure valve lash with engine stone cold. Post results.

Good luck!

 

Yeah I'll check that and post results. I have a few other things I'm going to check too.

 

My engine builder steered me clear of stroked FIs idk why but flat out said no to me, money in hand an all. BuT my application for DD might be different then you.

GL!

Personally, it's not enough info . . . But I'm not the smartest guy/gal here tho.
I have also never seen a lash go out that bad, that quick especially seeing it was good before the code. U can tell well before it's that bad, and it will be "rough" for awhile until it gets un manageable.

Everyone will jump to answer with lash because that's literally a troubleshooting procedure for rough idle, your case sounds different tho. Especially with just 2k. Like I said not enough info but to help even if you fully rebuilt the engine I'm saying short block and cams n all, if lash and everything else was new there is no reason lash would be that far out by now. Take it easy, take it to someone or you go over everything again before romping on it.

 

Yeah I still have to check and see if it's getting spark and fuel in the cylinder. I really don't think it's valve lash but I'll check it anyway. Like I said the car was running great and then it got a barely noticeable misfire and the CEL and now won't start and that all happened within a day and a very short five minute drive. So it happened fast.

As far as the engine being stroked goes it wasn't built by just any builder. InlinePro builds these all the time and have a lifetime warranty on their parts, machine work and assembly. Only thing they don't cover is like detonation from a bad tune or something. They're the only ones I would let do it and they're the best at building S2000 engines IMO. Jeremy Allen has been doing it for a long time.

I just can't figure out why it won't start but like I said I still have to get some time to get off into it and figure out what's happening. I just know the misfire and now not being able to get it to start has to be related.

 

Oh and another thing I'll add is that when I try to start it and it's cranking it doesn't sound like it's trying to start at all, so whatever is happening isn't just one or two cylinders but is affecting all the cylinders. It's turning over, it's just there isn't even a slight hint that it's trying to start and fire up. Just cranking.