Randon Misfire sometimes studdres and gimp mode others not

[hellotbone]

OK so drive my car 3 days and no RM today all of a sudden 3 times I get it. So 2 times my car would start to really mis and run like crap and shake like crazy, now the other time it just ran normal but thew the light. Now my question is why does it start to mis and studder.

I have 2 ECU's so I swapped to my other one to see if it will get the RM as well at least its worth a try before sending one of em off for link to get installed as both my ECU's are E proms.

 

[ziggi's92tsi]

sounds like it maybee runing to rich. what kind of fpr are you running, if you are running a stock one the diaphram may be bad and your fp is going crazy or it just can't bypass enough fuel.

 

[DSMTurbos]

you just put a 6 bolt in it right?

welcome to the world of random misfires, get dsm link or try the potentiameter sp? fix

 

[hellotbone]

you just put a 6 bolt in it right?

welcome to the world of random misfires, get dsm link or try the potentiameter sp? fix

Ok I'm well aware its random misfire my question is why does it sometimes studder and run like crap and trip the light and other times trip the light but run properly?

Secondly I have installed my OTHER ECU I have two. If it persists I will get dsmlink however before sinking money into it I wanted to make sure that this how the RM works in that sometimes it runs like crap and trips the light other times not. Also to get it to run proplerly again you must shut the engine off then on again.

 

[Scrymerr]

Ok I'm well aware its random misfire my question is why does it sometimes studder and run like crap and trip the light and other times trip the light but run properly?

Secondly I have installed my OTHER ECU I have two. If it persists I will get dsmlink however before sinking money into it I wanted to make sure that this how the RM works in that sometimes it runs like crap and trips the light other times not. Also to get it to run proplerly again you must shut the engine off then on again.

In order to cure the phantom random misfire problem using the potentiometer, the barometric pressure has to be below a certain value. On a day where the barometric pressure is already very low, the amount of resistance you need may not be very much. However, on a day where the barometric pressure is high, the amount of resistance you used may not be enough to decrease this value to get it below where it needs to be. Just buy a small resistor, solder that in as well, retune and see how it works.

 

[hellotbone]

I would prefer not to do the Pot mod because of the AFC settings being out so much some says at high at going from -30% back to 0% to get back to tune.

Here is what I am after does DSM link just keep it from getting the light or will it keep it from starting to studder and run like it is misfiring?

 

[Logue]

dsmlink will completely stop the ecu from looking for any of the values that start RM.

i have been fighting with RM for a year now.

anytime i get a RM while driving i just clear the code on my logger and it will go away for the rest of car ride maybe even a couple days if i am lucky. i noticed i get in a couple certain spots everytime i drive there. if i stay at a constant speed than start to drive up an incline or a decline without changing speed at all i will get RM. IDK its wierd.

The crank signal the CAS gives just isn't strong enough i guess for the ecu To read it. And it gets messed up somewhere.

 

[ADrewzki]

Do you have a pocketlogger? I'll bet that when it's throwing the light and the car isn't studdering, it's not due to misfire. When the car misfires, the ECU retards the timing so that's what causing your engine to shake and the loss of power. Personally, I haven't had very good results with the potentiometer mod. It just leaned out my engine and I still got the same frequency of random misfire. I've noticed that over time, it occurs less. Get a pocketlogger for now and save up for dsmlink like I'm doing.

 

[DSMTurbos]

if you don't want to do the pot fix then you have to go with dsm link. there is no way around it.....


dsm link turns off the ecu check for rm, the ecu code, i guess you could say, is turned off to ever check for it

 

[hellotbone]

Thanks guys the other ECU still sees the RM so I guess its still there. Im gonna send off for DSM link I was holding off till I tested this ECU.

On a side not I have a small knock in my engine when you initially rev it which I can't tell if it is piston slap rod knock or possibly fuel knock with the big injectors.

 

[BISHILVR]

im wondering why keydiver can't turn off the ecu code to check for rm with one of thier chips....?

 

[BISHILVR]

on the other hand there are people out there that have continued using the 7bolt cam and crank sensor setup on the 6bolt block with some modifications, im not sure what all is involved with that though, but i'd really like to know.......

 

[ADrewzki]

on the other hand there are people out there that have continued using the 7bolt cam and crank sensor setup on the 6bolt block with some modifications, im not sure what all is involved with that though, but i'd really like to know.......

I would imagine you just mount the sensor rotated a little bit and plug it in as normal. I think the timing marks for the 1g vs 2g is about 90* clockwise (give or take). It'd be nice to do and would make the swap work more smoothly afterwards.