Hesitation/Missing

12891 Views 32 Replies 5 Participants Last post by Cheezit, Sep 6, 2014

G20Tyler

Discussion Starter · Feb 27, 2014 (Edited)

I have recently acquired a good tune from a friend. My P11 is swapped with an SR20VE 5spd - I am having problems with revs dipping below idle speed when clutch is depressed, and I am getting random soft misses/hesitation when I am accelerating at WOT sometimes.

The problem is like this with the revs dipping when clutch is depressed -
http://www.youtube.com/watch?v=6R5QlBCksrg

For problem #2 my idea is that it could be a faulty front o2 - I have a crappy Bosch one and the wires are exposed, or that its is a timing issue, so I should advance the timing to clear up the hesitation.
Couldn't find a nissan vid but heres one of an integra doing the same thing.
http://www.youtube.com/watch?v=Nsm9SekQVHw

I should also add that cylinder #4 ran for 5 minutes flooded with fuel by an open injector. So I'm really hoping that didnt cause damage to the bore/ring causing all the problems...

1 - 20 of 33 Posts

ebinkerd

· #2 · Feb 27, 2014

Do a full blown tune up. Use bkr7e spark plugs too. new cap, new rotor, ohm out the wires, if they are good keep them. Also, remove the IACV and clean it out with brake clean. Once all that is done, reset timing to 15 then set base idle. And once you get to this point, if there is still an issue, begin the troubleshooting.

G20Tyler

Discussion Starter · #3 · Feb 28, 2014 (Edited)

I'm going to do timing when I get a chance, it is so random on the drive home almost no hesitation whatsoever, and I was driving spiritedly; car was pulling amazing.so I'm baffled. I'm sure setting idle, timing will be good, I haven't done it ever on this engine, we sort of plugged it in and stuck the dizzy at halfway and its been ok, iacv has never been cleaned either, I'm sure fit needs a cleaning after the flooded cylinder. MY TPS checked in at .389 volts too. If i remember correctly .375 is the allotted voltage.

EDIT: I have a shitty bosch front o2 on my header right now…. obviously that doesn't help at all.

G20Tyler

Discussion Starter · #4 · Mar 2, 2014

This is part of the problem I'm having, this has something to do with the random hesitation i get, when I let off the throttle the rpms increase then go down to idle. If I do this coming to a stop, when i depress the clutch rpms drop below idle, and rev up for a second, then back to normal idle speed. This also happens at very light throttle, it will do this in gear which i believe is why I am mistaking it for being hesitation when really its the throttle fluctuating.

http://www.youtube.com/watch?v=5poiSpzyfRI

javcrodgz

· #5 · Mar 2, 2014

Timing is something you would have wanted to set before tuning.

UNISA JECS

· #6 · Mar 2, 2014 (Edited)

That's looks to me from a tuner stand point like an incorrectly set TTP Min (Total Theoretical Pulsewidth Minimum), it would really help if you had a wideband to show the AFR when this occurs, I'd bet its a very rich dip 11-12 AFR for a brief moment. There so much in terms of tuning but glad to have little discussions on it on this forum since it is such a rare thing. I will say it is a little more hard to get the OBDI ECU to idle rock solid vs the OBDII ECU that's for sure but it can be done.

I can easily mimic that idle on my P11 if I want to so I know what can cause that type of dip, but for starters make sure at the very least but most important that BASE IDLE/TIMING are set correctly as well as TPS voltage before you can even start to tune.

p.s. fix that o2 sensor problem if in fact it is a problem that's very very important to a lot of things when it comes to tuning, I would like to see what your fuel trims are if you can video that if you have a way to monitor that.

UNISA JECS

· #7 · Mar 2, 2014

Here's what a proper "return to idle" after blipping the throttle should look like idle when the "tune" is correct and the "fuel trims" are "100% +/- 3-5%" but at idle mines pretty much rock solid 100% spot on.

This video is with my Nistune OBDII ECU setup by the way and 480cc injectors with Z32 MAF and everything else sensor wise running 100% perfectly. I just edited the contrast of this video so that the Air Fuel Ratio's can be seen more clearly hopefully on the Innovate LM-2 wideband display, you may have to open it up to full size to see the AFR values.

G20Tyler

Discussion Starter · #8 · Mar 2, 2014

Yes! That is perfect example of what I need in regards to idle return! I will say, I have seen this tune work flawlessly on an nx2000 with exactly my setup minus a full exhaust. I think the tune is rather solid, its likely to be calibration on my side of the field. I need to purchase a wideband I just have not had the money to do so unfortunately. Right now I am running an OBD1 stepdown to a 99' harness.

I was unable to set the TPS anywhere above .4v closed because everytime i tried to do so the idle would never come down from 1500, for driveabilitys sake I was forced to adjust it back to .35v closed I was only able to get a WOT reading of 4.12v also, from my knowledge it should read 5v if im not mistaken.

I am running open MAF also until my filter and adapter arrive in the mail, but i have re grounded the maf to the chassis and checked voltage and resistance, things read out just fine.

I figured why not clean the IACV for the hell of it some I'm going to do that today.

UNISA JECS

· #9 · Mar 2, 2014 (Edited)

8

G20Tyler said:
Yes! That is perfect example of what I need in regards to idle return! I will say, I have seen this tune work flawlessly on an nx2000 with exactly my setup minus a full exhaust. I think the tune is rather solid, its likely to be calibration on my side of the field. I need to purchase a wideband I just have not had the money to do so unfortunately. Right now I am running an OBD1 stepdown to a 99' harness.

I was unable to set the TPS anywhere above .4v closed because every time i tried to do so the idle would never come down from 1500, for driveability's sake I was forced to adjust it back to .35v closed I was only able to get a WOT reading of 4.12v also, from my knowledge it should read 5v if i'm not mistaken.

I am running open MAF also until my filter and adapter arrive in the mail, but i have re grounded the maf to the chassis and checked voltage and resistance, things read out just fine.

I figured why not clean the IACV for the hell of it some I'm going to do that today.

Things I see wrong:

Not being able to set your TPS between .45 - .55v = FAIL get that right you don't have a choice!
(4.12v WOT is correct by the way.....it should NEVER read 5v at WOT)

Here's is why you have to switch to a P10 LP TB because its impossible to run the correct TPS sensor (same sensor used on B13 and B14 pre 97) on a P11 TB I don't care if you can get the correct voltages or not, switch the TB and sensor.

If you are running a N62/N60 MAF the second ground wire need to be grounded to the intake manifold at the sensors ground location (F15 or F16).

This is the pin and ground wire that need to be run to engine ground at location F15 or F16 from above schematic

I'm always weary of people running "step down harnesses" cause they simply don't do them correctly sometimes but I cannot comment on that really.

Did you swap your throttle body yet because you know you cannot properly use a P11 TB with an OBDI ECU right, you need to run a P10 lowport TB.

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G20Tyler

Discussion Starter · #10 · Mar 3, 2014

Wow I had no idea the 99 P11 throttle body/tps didnt work well with obd1. I will be on the lookout for one at the JY! I got the tps voltage to read .5v closed and i adjusted my idle back to normal via the unplug-adjust screw-plug in method. Hesitation still occurs at random - i am going to do timing later this evening.
P10 throttle body and tps will be on my to do list.

I also grounded both MAF wires together and spliced a chassis ground into them, I will try your grounding method.

UNISA JECS

· #11 · Mar 3, 2014

G20Tyler said:
Wow I had no idea the 99 P11 throttle body/tps didnt work well with obd1. I will be on the lookout for one at the JY! I got the tps voltage to read .5v closed and i adjusted my idle back to normal via the unplug-adjust screw-plug in method. Hesitation still occurs at random - i am going to do timing later this evening.
P10 throttle body and tps will be on my to do list.

I also grounded both MAF wires together and spliced a chassis ground into them, I will try your grounding method.

They way I ground my MAF is just the right way to do, its the way its done from the factory as well, the proper way, see one ground wire is for the MAF sensor, the other "ground" is actually for the shielded wire that is protecting the MAF signal wire.

Here is a youtube video that shows the importance of this granted this is much higher voltage being worked with but you should see the importance clearly of using and more importantly ground this "shieled" cable correctly which is what my whoel point is.

G20Tyler

Discussion Starter · #12 · Mar 3, 2014

So I attempted to adjust the ignition timing, entering timing mode was quite irritating. Using the timing light the timing was fluctuating all over the board from -5 - 25 degrees timing, getting it steady at 15-17 was a challenge, and once i finally had it adjusted there the minute you plug the tps back in the timing set itself back to 5 degrees. Gonna go ahead and grab the P10 tb tomorrow morning as well. As of right now the timing is somewhat ok im not even sure where to really is at but i know on partial throttle i can feel it moving around lol, at WOT it remains stable, runs like a champ, anything on the midrange causes retarding.

UNISA JECS

· #13 · Mar 3, 2014 (Edited)

G20Tyler said:
So I attempted to adjust the ignition timing, entering timing mode was quite irritating. Using the timing light the timing was fluctuating all over the board from -5 - 25 degrees timing, getting it steady at 15-17 was a challenge, and once i finally had it adjusted there the minute you plug the tps back in the timing set itself back to 5 degrees. Gonna go ahead and grab the P10 tb tomorrow morning as well. As of right now the timing is somewhat ok im not even sure where to really is at but i know on partial throttle i can feel it moving around lol, at WOT it remains stable, runs like a champ, anything on the midrange causes retarding.

Imma say you didn't enter timing mode cause once you do its locked pretty much rock solid and base idle and timing both go hand in hand, make sure your rpm are ~850rpm and you'll need a timing light that shows rpm digital or consult w/laptop and something you can read it with cause the stock rpm cluster is quiet off if you ever compared them to actual rpm.

If you cant get it to go into timing mode download the Conzult freeware version in the link below and it has a timing/base idle mode that makes it a smap to do with out having to do the rain dance.

Click on the download tab on the left side of screen

Conzult freeware version

G20Tyler

Discussion Starter · #14 · Mar 4, 2014

2

Picked up the TPS and throttle body, will I need a manual TPS or will the automatic work as needed?
Pictures below:

Now, if I can use the auto sensor, will I need to do anything funky to the wiring or can i just solder it to a new plug to its appropriate pinout?

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UNISA JECS

· #15 · Mar 4, 2014 (Edited)

If your 5 speed you need a manual TPS that one in the picture will not work. You don't have to do anything extra just plug it in once you get the 5 speed TPS.

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G20Tyler

Discussion Starter · #16 · Mar 4, 2014

Ok the search continues…. *dun dun dun! Good thing i only paid for the TB

haha

UNISA JECS

· #17 · Mar 4, 2014

G20Tyler said:
Ok the search continues…. *dun dun dun! Good thing i only paid for the TB haha

Well you can get that 5 speed TPS from any 5 speed B13/B14 up to early 97 and any P10 lowport or highport.

G20Tyler

Discussion Starter · #18 · Mar 6, 2014

UPDATE: Cleaned my P10 throttle body, gonna pick up an NX2000 5spd TPS tomorrow or today. Reground maf differently and we shall see. I want to try doing timing one more time, maybe hook up to consult at the dealer and adjust base idle if I can get one of the homies to get me some time in the service bay.

G20Tyler

Discussion Starter · #19 · Mar 9, 2014

Alright Charlie I put the P10 tps on and throttle body etc. I still get lumps of hesitation, now all thats left would be the o2 sensor.

UNISA JECS

· #20 · Mar 9, 2014

G20Tyler said:
Alright Charlie I put the P10 tps on and throttle body etc. I still get lumps of hesitation, now all thats left would be the o2 sensor.

Good your running correctly now you can find the problem

Did you set your TPS between .45 - .55v at closed throttle and are you getting 4.1v WOT.

Can you also provide your .bin AKA your tune, do you have a way to pull your tune of of the ECU?

I can almost bet money you just have a shitty tune, but your tuner should have also caught that you were running the incorrect TPS and im sorry to say but no tune gets if the ground with a faulty o2 sensor also or for that matter any sensors that are bad period with me, everything effects a tune, a good tuner knows this.

1 - 20 of 33 Posts

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