mx5cartalk.com

Ok, ive read about similar problems before but can't find exactly what it could be.

posting to get other people's opinions.

ok

Symptoms:
As I accelerate I can notice a substantial power loss in the car. Noticed it last Saturday night when going on a hills run. The car seemed a little more sluggish than usual.

Yesterday as I was driving home, I was in 5th gear at around 2000rpm when the engine started what seemed like stuttering. Seemed like one of the cylinders wasn't firing.

Similar problem to what I had a few months ago when water got in to one of the cylinders. Just wasn't firing right.

The car sounds more like a 12A rotor puffing and dumping fuel surging the car forward in waves rather than a smooth gradual acceleration.

I'm thinking my leads are dying.

The spark plugs when I pulled them out are BLACK.


usually there still whitish in the middle... not its just covered in carbon.

What i've checked so far:

Timing seems to be spot on. Gears and belt haven't slipped

CAS looks good, no water and the connections are fine

coil pack looks good too

checked for spark out of each lead and its sparking

any ideas?

yeah sounds like leads to me.

leads are fine

the engine was running excessively rich.
all fixed.

im happy

only took a whole day to figure out.

http://www.spark-plugs.co.uk/pages/tech ... gnosis.htm

http://www.dansmc.com/sparkplugs1.htm

have a read.. interesting way of diagnosing a problem.

cost me nothing to fix it all up.
thats the bit that im happiest about

so how did that happen & what you do to fix it?

With either of those links you haven't actually told us what the problem was.

that spark plug shows how rich it was running.
spark plugs should be a browny colour
much guess is that it was running to rich causing the engine to flood rather then to combust?

we all know it was running rich, question is why

Taken from a previous post. Astro sold his DFA and replaced it with the following. Assume something went amiss with the e manage and/or input?

Astroboysoup wrote:i got my e manage blue for about $500 inc cables.

J

oh sh*t.. i have to post the DFA off...
richee is gonna be angry....

if you're reading richee im covering it in bubble wrap as i post

ok problem was with the timing and the HKS VPC

I use to have the e-manage but i sold it to Uncle Arthur with the turbo kit that i sold him.

I shouldn't have.. would have made my life with the HKS VPC much easier.

After the dyno day I had it tuned pretty much on spot. but for some reason i decided to turn it back to 10 degrees rather than the 14 that it was on.

so i turned it back to 10 but I didn't change the tuning on the VPC. makes a huge difference.

Leaned out the fuel mixture and then bumped the timing a little bit.

got it running smooth again and spark plugs are back to normal.

I need piggy back ecu that can do ignition, injection and air flow.

I think I do need the DFA still.. oh well.. sold now..

Astroboysoup wrote:
I need piggy back ecu that can do ignition, injection and air flow.

I think I do need the DFA still.. oh well.. sold now..

megasquirt

you're a handy guy. you biult the dfa so you can build a megasquirt. it is a lot more complex , takes longer to build and wire into the car, but offers much greater control .

still haven't finished mine tho . i'm a bit stuck on the wiring it in part, but i'm sure with a bit of time and research i'll figure it out.

but got more important things to work on at the moment. and the dfa is doing the job just fine anyway in the meantime.

yeh i thought about the mega squirt..

the DFA was easy to build

the MS looks alot more complex. dunno if i can handle the frustration and tedious task of checking each and every join and resistor in such a big circuit.

Emanage Ultimate would be a much easier plug and play option for me.