S300 on P28 problem please help!!!

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luky1380

New Member
Hi all
I installed S2Pro1 cams and got used hondata S300 on P28 OBD2B ECM
took it to the friend of my to tune it spent few hours on the dyno and everything went well to the point when we went for road test. Few minuts on the road and car starts sputtering (A/F was going to 10.0 at that moments) then CEL came on and car went to limp mode(2000rpm and rich) we put laptop to it and it gave 3 codes: IAT, TPS and CTS got them reset star the car up let it idle for like 2min and same thing limp mode with same 3 codes. put it on the live data and looked for those sensors: colant temp was jumping from 150to205 and was offline few times, IAT looked steady, TPS looked steady to the point to the point when it goes to limp than it stays locked at 25%opened ones it jumped to like 108% and car stall
And i never had this problem with my old ECU(had a PCT)
Is it bad P28 or i have to look at something else ???
Thanks for any replay
 
Anyone help please
Installed stock P2T ecu drove all day and had no problems
I know someone knows it any advise will be nice
 
Try without the cams?

:confused:Without cams???:confused:
I dont see any reason that cams will do that (set codes for IAT ECT TPS)
plus it runs good with JDM PCT ECU and stock P2T ECU
my bet is on P28 maybe someone who converted it from OBD1 to OBD2B messed up wiring or some...or maybe i need to do some with wiring???
Any other ideas???
 
I am confused why a OBD1 P28 would ever be converted to OBD2B.....didn't even think it would be something anyone would want to do anyways. Now a Jumper Harness......yes.

I say you talk with Hondata and rock another ECU for now. They are just Skunk2 Stage One anyways......only way to get more out would be to dyno tune with that S300......get it checked out by Hondata and go from there.

If you are NOT popping codes with other VIRGIN ECU's.....it must be something wrong with the S300.
 
^that is a point, but my other point is the cam lobes are maybe too thick for your valves the way they are lashed, i've seen it before where it will just kill everything and it'll sound like your hitting the rev limiter at a very early rpm, then limp everything.
 
Well.....I guess I was assuming he re-did the valve lash when he installed new cams.....plus it sounds like it is only throwing codes with one ECU but doesn't with two other ECU's
 
I am confused why a OBD1 P28 would ever be converted to OBD2B.....didn't even think it would be something anyone would want to do anyways. Now a Jumper Harness......yes.
yes i know i was pretty surprised my self when i got it, it says P28 OBD2B and it is plugs in to stock harness

I say you talk with Hondata and rock another ECU for now. They are just Skunk2 Stage One anyways......only way to get more out would be to dyno tune with that S300......get it checked out by Hondata and go from there.
I did they told me that i need laptop hookedup to it and it needs to be in when ecu have error and it hard for me to do dew to the work hours

If you are NOT popping codes with other VIRGIN ECU's.....it must be something wrong with the S300.
i was thinking of that but the guy who tuned it (he is hondata dealer) told me that hondata can't command ecu to keep TPS sensor open at 25% when it in limp and only ecu it self can do it
 
and sorry i didnt put any info on the car
its 00 civic si B16A2 cai, full exhaust skunk2 pro1 cams supertech valve springs 255 wolbro fuel pump
 
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^that is a point, but my other point is the cam lobes are maybe too thick for your valves the way they are lashed, i've seen it before where it will just kill everything and it'll sound like your hitting the rev limiter at a very early rpm, then limp everything.
it doesn't sound like it hits limiter its just sputters and jerks and and runs to rich and when it sputters you can smell gas and im not talking about like it runs rich im tolking about distinct fuel smell
 
Well.....I guess I was assuming he re-did the valve lash when he installed new cams.....plus it sounds like it is only throwing codes with one ECU but doesn't with two other ECU's
thanks CAFROG
of course i adjusted valves lash when i put cams and after 500mi again and plus car did well on the dyno for 3hrs and made a good power it was almost 146 on dynojet and only after we took it for road test hell broke lose
 
Roll the stock B16A2 ECU for now. If it doesn't throw codes or (better yet) don't limp.....use it for now.

Is the TPS sensor held on to the throttle body by rivets or torx or phillips or?? Have you multimeter tested the TPS at closed and wide open throttle??

So you have no jumper harness and your OBD2B plugs right into some OBD2B ECU that says P28???? That's some cracked off $hat.
Well......I did once buy a USDM OBD1 P30 that had the legit sticker but I cracked it open to find out it was chipped and sent it back.

I am not knowledgeable enough about Hondata but I wonder if you can get a P28 (or maybe a cheaper P06) and have Hondata transfer the S300 onto the new ECU?
 
thanks CAFROG
of course i adjusted valves lash when i put cams and after 500mi again and plus car did well on the dyno for 3hrs and made a good power it was almost 146 on dynojet and only after we took it for road test hell broke lose

From my knowledge......146 is on the low side of a basic B16 with 3 bolts.....no cams, springs, tune. I have seen them hit low 150's.......how is your compression??
 
Roll the stock B16A2 ECU for now. If it doesn't throw codes or (better yet) don't limp.....use it for now.

Is the TPS sensor held on to the throttle body by rivets or torx or phillips or?? Have you multimeter tested the TPS at closed and wide open throttle??
ya thats what im doing now rolling on stock ecu and yes i checked TPS for voltage and everything checked out normal (from 0.4v closed to 4.98 wide open)

So you have no jumper harness and your OBD2B plugs right into some OBD2B ECU that says P28???? That's some cracked off $hat.

I am not knowledgeable enough about Hondata but I wonder if you can get a P28 (or maybe a cheaper P06) and have Hondata transfer the S300 onto the new ECU?
yes stock harnes plugs in to P28 ill snap few pics in the morning

and yes hondata can do that for like $80-100 some in that range and i already was thinking about it
 
From my knowledge......146 is on the low side of a basic B16 with 3 bolts.....no cams, springs, tune. I have seen them hit low 150's.......how is your compression??
hmmm... when i bought cams from kingmotorsports they told me that with cai and exhaust and those cams ill be looking close to 150 range and if ill go up in compression somewhere to 11.8-12:1 range i can get close to 170 range and belive what they saying because they are long known company and they build test and race alot of hondas and acuras
and I dont remember numbers on compression it was good 3 month ago and leakdown test was good too it was only like 5-10% on all 4 cylinders
 
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