kylelind

So I just installed my new MSPNP and am experiencing misfiring. I think that I had a tiny on the stock ECU but nothing this bad. Before it was just a slight jiggle every once and a while while sitting at a light. Now with the MS installed it makes the RPM drop a lot sometimes while at idle. It misses a ton when colder and not as much when warmed up. Any ideas as to what may have caused this. It makes the exhaust smell very very rich....like burn your eyes sometimes.

One though is bad plug wires because mine have some small flakes of rubber missing from the housings, which I though could be from arcing. Can the coils get frapped just from installing the MS? Also right before I pulled the old ECU it had code 16 "EGR function sensor"......who knows.

Let me know what you think, and the car is bone stock, very well maintained.

cjernigan

iTrader: (13)

You need new plug wires. Unshielded wires that possibly or do arc will cause misfiring.
You also need to clean the ground wires on the engine up by the throttle body.

FoundSoul

iTrader: (5)

Is it just idle misfire that you're noticing or any other behavior you're concerned about?

Either way go ahead and replace your plug wires-- if they're old enough that small chunks are falling off of them then that can't be a good thing. Maybe new NGK plugs too.

Have you done any tuning of your VE table yet, especially around idle? Do you have a wideband? If it's leaner than about 13.3-13.5:1 at idle you'll likely get slight misfires... Too lean and they'll be bad.

And that can cause the raw fuel smell even though we're talking about being too lean-- as the misfire itself will spew raw fuel into the exhaust which would be what you were smelling.

If you don't have a wideband tune your idle VE for lowest MAP pressure. adjust the area around where you idle somewhat evenly to help it stay stable (if you need to lower the ve, lower all of the idle areas 1 point at a time, use multi-cell select to make this easy).

kylelind

sorry but, what is VE?? And also whenever I push in the clutch while driving the RPMs bounce about 800rpm four or five times before smoothing out.

cjernigan

iTrader: (13)

VE is your fuel map.
Have you read the manual yet because VE is a pretty basic part of MS?

FoundSoul

iTrader: (5)

Sounds like you've completed the Plug part of Plug-n-Play, now onto the Play part-- that means fine tuning for your car. Then you get to really play. The base map is REALLY close, but each car will vary a little. The manual goes over this several times that fine tuning is very highly recommended. In addition to reading the MSPNP manual I recommend reading the MS1 Extra manual that gets installed with the software CD. It will go into all the basics of what a MegaSquirt is and does and how to get the most out of it. Note it's coming from a DIY perspective of having to build/mod/wire it all up. The MSPNP takes care of all that for you, and 95% of the tuning on an n/a application-- you've just got to fine tune it. A massive amount of work has gone into making your experience as smooth as possible, as much as could be done from here- you've just got to take it that last few yards to the goal line. We will be glad to help from here-- work with our support team, let us know what you're seeing, and we're glad to help. We'll review datalogs, suggest settings, etc. We can't tune your car remotely, but you'd be surprised what we can find in a datalog sometimes.

As for your idle- I may have some settings to try that could improve it a bit. Shoot me an email and I'll send you screenshots of the test settings. It will sometimes oscillate a tiny bit before settling in, but the updated settings that I'm testing seem to be a bit better and more stable than the base map. Once I confirm that for sure I'll release an updated base map.

kylelind

I have read the manual and do know that I need to tune more, but have not had time to figure it out. I have been spending all of my time ordering parts. I just finished that and will get the car running good before turbo install. Sending email FoundSoul.

FoundSoul

iTrader: (5)

Ygm

Arkmage

iTrader: (3)

my MS was doing the same kinda crap last weekend after running fine for months. I traced it down to a bad connection in my switchbox. (if I bypass the switchbox for injector bank 2 the problem goes away). So it's possible that you have a bad connection/wire somewhere as well.

Something to consider.

FoundSoul

iTrader: (5)

He probably would have noticed that equally with the stock ECU. He mentioned feeling a miss with the stock ECU, but said it was worst with the MSPNP. We them out on a running car so it's not the MSPNP. The miss with the stock ECU is likely the wires/plugs maybe. The fact that's it's worse with the MSPNP is likely that it's not fine tuned for his car and I bet it's a bit lean...

kylelind

Yeah, maybe lean but I dont have the wideband in yet so who knows?

FoundSoul

iTrader: (5)

At idle, tune for best MAP (lowest kpa which is highest vacuum), that will usually get you pretty close.

cjernigan

iTrader: (13)

When is the wideband going in?

kylelind

could go in this week, but maybe not until I tear it down for the turbo....

kylelind

Here is a pic of the plug wires that have unusual flakes missing from the housings:

http://i243.photobucket.com/albums/f...d/IMG_1511.jpg

kylelind

Ben

iTrader: (33)

so...
you have misfires
and your plugwires look like that

hmmm

FoundSoul

iTrader: (5)

I'd definitely replace those, and go ahead with new plugs while you're at it. For a little fun start the car in a garage at night and turn the light out, I bet you can see sparks jumping across the wires .

kylelind

Ohhh, sounds like fun, maybe a movie. I just wanted others to see the problem so they too can fix the problem. My new wires should be here wednesday!

kylelind

So, I did start the car with the lights off and no sparks??? Today I also installed the new plug wires and I still am getting misfires. Could it be the coils? they are 11.5k and 11.79k Ohms between the output terminals? I really want to solve this issue before the turbo goes on. What else could it be?