F20Cdriver

p1399(manufacturer control ignition system or misfire-pending)

p1259(manufacturer control fuel air metering)

engine will not idle immediately, i have to leave my foot on the accelerator before it will idle on it's own. when it does idle, it's very rough. i can also hear noise where the timing chain would be. i opened the valve cover to see if there was anything obvious to a novice such as myself, but no luck.

mods:
cylinder head
(port and polish, valve job, supertech valves, supertech retainers, supertech springs)

block
(cp pistons 9:1, benson sleeved, benson micropolished crank, pauter rods)

replacement parts:
oil pump
oil pan
timing sprocket
timing sprocket bolts
cam gears
knock sensor
engine mounts and stoppers
ignition coil for #3 cylinder


somebody please help...it would be much appreciated!

RED MX5

What ECU are you running? Who did the tuning?
What events preceeded the appearance of the codes?

F20Cdriver

[QUOTE=RED MX5,Feb 9 2008, 01:45 PM]What ECU are you running?

RED MX5

Have you contacted Mike Laskey to see if he might be able to help?

The noise you're hearing in the timing chain area worries me, but if the engine is missing badly (and it sounds like it is), the noise could just be the result of the way the engine is running. Is the misfire regular, or irregular?

Honestly, with all the work that's been done on the engine, I'm grasping at straws.
Check the obvious stuff; Compression, spark, and A/F.
Sorry I can't be more helpful.

F20Cdriver

i called up mike laskey and he's being as helpfull as he can without actually working on it himself. he lives in aneheim and i live in san diego. i'm not a mechanic and surely not a tech, but i think i'm just going to have to tackle this thing on my lonesome. i have the s2k service manual on a cd, so i'll do what i can with that. thanks for the help man...i appreciate your time.

f20kills

I could be wrong, but with those mods I would think you would need an aftermarket ECU.
AEM EMS
I would assume thats your problem. It could make things worse if you do need a EMS and youre running the stock ECU.

F20Cdriver

i think you're right, i have to save up some cash though. one mod at a time.

RED MX5

But the car has been driven for 651 miles on the current setup, and was (apparently) running OK for a while.

plokivos

uh... you lowered the engine compression, have a built engine and you're running on stock ecu?

well, that's the problem. you're probably running like crap right now, misfiring and afr is probably all wrong.

that's nutz... how do you drive 650 miles on a stock ecu with lowered compression???

i bet your knock sensor got tired of trying to stay alive anymore.

you should of bought an aftermarket piggy back or ecu before you started to drive this thing or start modding it.

dang.... benson sleeves too... damn it, you're driving on an engine that I want and you're screwing it up!

RED MX5

How was the car running during the 651 miles you drove it? At that time, was the stock ECU in the car? Was it throwing any CEL's?

Is Mike aware that you're running the stock ECU? Does he think it should work OK with your setup?

It's not that far from San Diego to Aneheim, and if Mike thinks the car should run OK with the stock ECU, I'd have the car towed up to his shop and get him to figure out what's wrong. With all the work that's been done to the car it could be almost anything, and frankly, I'd have to see the modified engine run on the stock ECU before I'd believe it. I'm not saying that it's impossible, but just that I'm skeptical and would have to see it to believe it.

The stock ECU will modify it's maps (it "learns"), and will work fine with changes like IHE, but dropping the CR to 9:1 is probably outside the range that it can cover. If that's the case, then the ECU should have thrown a CEL during that 651 miles of driving. So, did you not see other CEL's prior to the current round of problems?