i have obd2 gsr currently running on a gsr base map chipped p28, if i drive the car for a while, my idle starts to go up and down between 750-250,
Is my best bet to have the car tuned with the p28, or tune a p72? i dont think its a vaccum leak cause it would do it from the start.

 

I have a b16 with a b16 basemap chipped p28. I also noticed the idle bounce. I changed the IAVC with no luck. I replaced my PCV and my idle dropped to normal. You may want to check that.

If there is an issue with using a p28 chipped ECU would be great to know.

 

my buddy who did the swap for me, is saying to get it tuned and all that will go away? i know that with every swap you should get it tune it to the car, however is that the only soloution? checked my pcv on my buddys car and its ok

 

i'd choose the p28 over the p72.

 

Will a stock P28 run a stock GSR?

 

it could but not correctly, it would run the gsr like a z6

 

Get a tune it should go away. my buddy has the same problem in his car

 

p28 is fine, all you loose in the nock function of the p72, and that is if it is enabled on the p72 when they tune.
Possibilities:
IACV
FITV
Vacuum low
Tune is not correct for your engine at start-up, which makes me wonder about the rest of the air/fuel and ignition tables.
Get it tuned!!!
Clean the other parts listed as it isn't that hard, and can find many write-ups on how!

 

cool thanx guys

 

P28 chipped rev at 8500 two step at 3500 vtec at 4500..... Eliminate the rest

 

It will run it but the secondaries won't open. Also the knock sensor won't get picked up as they stated before. That's pretty much it. It ran mine just fine. Then I had it chipped with Hondata and damn!!! What a difference. Then I just kicked the GS-R intake manifold to the curb and got a Skunk2 ITR one. I love it. It had to be retuned though so that it would run the secondaries.