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built motor sputters

Posted: Fri May 04, 2012 6:13 pm
by portmaster
Please help

2008 sI FG2

Built motor
Blueprint h beam rods
CP flat top pistons
ARP head studs
Cometic head gasket
ACL bearings
Stage 2 brian crower NA cams
Dual spring valve springs
Over sized valves .5mm over
Sidewinder manifold
T70 turbo
ID1000cc injectors

Ok so i loaded the hondata turbo 650cc base map

I noticed huge knocks on cylinder 2
I added fuel and pulled timing
still knocks
AFR is at 14
Car sputters in load columns 3 to 6 but if i go get into the upper columns it stops knocking and pulls hard
I pulled more timing and it still knocks

It sputters when i am trying to cruise and when it sputters cylinder 2 knocks sky rocket
I moved the plugs and coil around and the issue remains in cylinder 2

Any suggestions?

Thanks

Re: built motor sputters

Posted: Sun May 06, 2012 6:20 am
by Hondata
It probably is valve train noise, not knock. If you have pulled a lot of timing that could cause the hesitation. Post the calibration/datalog for more analysis.

Re: built motor sputters

Posted: Sun May 06, 2012 11:10 am
by portmaster
Ok, so i changed my can angle to 0 degrees on high and low and that took all my knocks away.

I locked my cams to 15 degrees and the knock and hesitation came back.

In my log my knock level comes up to 70% and it retards my timing 18 degrees

And it is only at 3000 and 3500rpm

before and after 3000 and 3500rpm the car runs great as long as i am accelerating i never see a single knock
If i try to cruise in that range knock knock knock

I do have some idle issues. I only have -16psi at idle.
Reading from 4 bar map sensor

I set my injector dead times to the 43psi setting and that helped my idle

But it will idle normal at 900rpm with 14.9 AFR then S.TRIM starts pulling fuel for some reason then the car almost stalls at 17 afr then S.TRIM jumps up to 15% adding fuel then levels out idles fine for about 2 minutes then does it again

Re: built motor sputters

Posted: Sun May 06, 2012 11:12 am
by portmaster
Hondata wrote:It probably is valve train noise, not knock. If you have pulled a lot of timing that could cause the hesitation. Post the calibration/datalog for more analysis.
I will post a datalog when i get home. Thank you

Re: built motor sputters

Posted: Sun May 06, 2012 3:32 pm
by portmaster
Hondata wrote:It probably is valve train noise, not knock. If you have pulled a lot of timing that could cause the hesitation. Post the calibration/datalog for more analysis.
Attached cal and datalog

The idle is at the end of the log file
PortMasterDatalog.fpdl
Calibration
Turbo650_2CAM.fpcal

Re: built motor sputters

Posted: Sun May 06, 2012 5:09 pm
by Hondata
I would check the valve clearance (some people check between the cam and follower rather at the valve stem) and then check the cam indexing using the arrows on the sensor plates at cam cap #5 (transmission end of the engine).
It it only happens in VTEC and get worse when hot then I would suspect valve/valve or valve/piston contact.
Otherwise limit the short term fuel trim to +-10% and reduce the knock retard values, both so that you can get some part throttle tuning done. With futher tuning it may improve.
Bottom line is that if the cams jerk the cam train around there is only so much you can do.

Re: built motor sputters

Posted: Sun May 06, 2012 6:55 pm
by portmaster
Hondata wrote:I would check the valve clearance (some people check between the cam and follower rather at the valve stem) and then check the cam indexing using the arrows on the sensor plates at cam cap #5 (transmission end of the engine).
It it only happens in VTEC and get worse when hot then I would suspect valve/valve or valve/piston contact.
Otherwise limit the short term fuel trim to +-10% and reduce the knock retard values, both so that you can get some part throttle tuning done. With futher tuning it may improve.
Bottom line is that if the cams jerk the cam train around there is only so much you can do.

Just fyi car pulls amazingly well in vtec and i have very few knocks at WOT
Some pulls i don't have any knocks at WOT

I set my fuel trims to 0 and 0 and the idles perfectly fine completely steady

would this be an indication of a bad factory o2 sensor?

how does the ecu determine when to use and or calculate fuel trims?
Your help is greatly appreciated :)

Re: built motor sputters

Posted: Tue May 15, 2012 11:51 am
by portmaster
Anyone able to answer my question/s?

Thanks

Re: built motor sputters

Posted: Tue May 15, 2012 1:45 pm
by Spunkster
I don't understand the question.

Would "what" be an indication of a bad 02 sensor?

Re: built motor sputters

Posted: Fri May 18, 2012 3:23 pm
by portmaster
random fuel trims at idle from one extreme to another ? From -10% to +20% S.TRIM for no reason... AFR is steady at 14.9:1 then it starts pulling fuel... goes too lean (almost stalls!).. then adds fuel to get it back. Then idles for a minute or two then pulls fuel again....

Re: built motor sputters

Posted: Fri May 18, 2012 4:00 pm
by Spunkster
How long is the down pipe from the turbo? How far from the turbo is the 02 sensor?

Re: built motor sputters

Posted: Fri May 25, 2012 1:31 pm
by portmaster
The primary o2 sensor is 32 inches from the turbo with a combination of two 90 degrees bends before it. 90 degrees off the turbo then another 90 degree to point down to the ground total of 32 inches.

I replaced the o2 sensor and it seems to have resolved the issue. Before I replaced the o2 sensor I did change the minimum fuel trim to -10% and that helped a lot.