Having a bit of a problem with a dc2 on hondata and wondering has anyone and ideas!

Its a built b18, 12.2(ish):1, toda Bs, springs etc etc,
The thing is, i tuned the car one day last week, all went well, afr just where i wanted it, went for the timing, did a few runs with the det cans till i was happy, car ran great, owner was happy!

On his way home, it started to splutter coming on vtec and would not pull through the revs!

I checked over everything in the map and tried changing a few values but it still persisted, the only way it would stop was if i started a fresh map!

so, it was left for a few days and retuned, again all went well, he was driving the car for a few days with no problems, then out of the blue, the same problem, i changed the coil and ignitor in the dizzy just to be sure but again the only way it stops is by changing to a different map!

has anyone came across this before, the guy is thinking of just switching to eCtune now because of it!

Any help appreciated!

 

Out of curiosity, did you disable the O2 sensor within Smanager? Sounds like an O2 sensor is trying to modify the fuel values when it goes into closed loop. Also, wouldn't be a bad idea to see if you can datalog what is happening when it starts having the problem.

 

closed loop was on the first time but off the second time, the problem is only when coming on vtec though so it shouldnt be in closedloop anyway!

i havent had a chance to get back at it to log any runs yet!

also, what would be the max timing you guys would run in wot, vtec with that type of setup, all our pumps are 95 octane here too! apart from the e5 which is 99!

 

You would need to provide a datalog of before & after the issues along with the calibration in order to get any kind of accurate feedback.

The issue simply "going away" once you start on a new calibration does not make sense at all.

Out of the hundreds of hondata systems I have sold & tuned I have never had any issues such as the one you are describing.

 

i know it doesnt make sense, thats why im here wondering if anyone else came across it!

uploaded a previous cal. to it today and it runs fine, i didnt have time today to put the WB in and log any runs, he has decided he wants to go with ectune now anyway so if it happens again before its swapped i will try get a few logs!

 

Do you have VTP disabled?

My guess is once the car heats up the oil viscosity gets thin and oil pressure is dropping keeping you out of VTEC on the cam, but running on the maps for VTEC.

 

i think you might have hit the nail on the head there chris!

he text me late the other night saying there is a rattle which sounds like a big end so oil pressure would explain alot!

VTP would have been disabled because its an obd2 dc2 itr so it does not have the VTP switch!

 

Chris, can you read tarot cards? lol

 

I wish!

I think I have seen EVERY problem that could possibly arise on these cars though...

But then of course I have another car tomorrow that will challenge me

Seriously I need to do a BLOG with these things as they happen!

 

I have seen a lot of issues but I have yet to see a car with inconsistent oil pressure such as the one described in this thread.

 

that could turn out to be a very helpful blog

but after thinking about your suggestion chris i thought about it some more and was still confused as to why id would run ok once the map was changed??

any ideas on that??

 

HI Chris. You're analysis is dead on. That is what I thought also.

Have you experienced losing VTEC because of the oil filter?