Plain Jane OEM nothing to see here rebuild

[JustJeff]

I've got the throttle thing sorted out. The throttle cable had too much slack on it.

My new problem is timing and fouling of plugs. My trailing timing does not line up. leading is dead on. Engine warmed up, RPMs around 750ish. TPS set to 1V in idle position. But trailing timing is advanced just about halfway between the leading and trailing marks.

I went through my ECU pins looking at voltage. I found a couple of oddities:

1) Clutch switch on the front of the clutch pedal was dead. I replaced that and confirmed the ECU is seeing a signal from it.

2) AC relay and A/C switch both show 12V whether A/C switch is on or off

3) Neutral switch shows no change at ECU between Neutral and in gear...but IIRC I do not have a neutral switch on my JDM transmission.

4) Oxygen sensor was way off, but that might be because my engine is running really rich??

It's supposed to be Idle-below 1V, Accel -.5-1V, Decel -0-.4V.

Mine idled at 29.6mV, I wasn't driving with DMM on, but I throttled the pedal Accel-22mV, Decel-26mV

5) The other oddity was my TPS narrow at first seemed to be dead. Even though it showed 1V at the sensor and shows a clean sweep. At the ECU it showed very badly 2.64V and never really changed much as the throttle changed. Before writing off my TPS I checked it again another day and it read dead on that time. I checked it at the sensor first. Then checked it at the ECU and it had the same reading....very strange. It might not have been backprobed correctly the first time, but I thought I checked it and double checked it.

6) Full range on the TPS is definitely off by a bit. It should read .8V at idle and mine sits at .54V. Can I get some feedback on that one? On the one hand off by .26V doesn't seem bad, BUT that is a significant amount when it's 1.4 of the total spec reading.

I have an Innovate wideband on it's way to me. I'm hoping to have it installed this weekend.

[RETed]

Originally Posted by JustJeff

1) Clutch switch on the front of the clutch pedal was dead. I replaced that and confirmed the ECU is seeing a signal from it.

When mines went bad, the engine tended to idle slightly higher than normal.

2) AC relay and A/C switch both show 12V whether A/C switch is on or off

I believe the circuit pulls to ground - the switch grounds out at the A/C compressor?
Also, I believe there's a pressure sensor switch (for safety reasons) is wired in series to the circuit...which could be the culprit?

3) Neutral switch shows no change at ECU between Neutral and in gear...but IIRC I do not have a neutral switch on my JDM transmission.

I know this affects the cold-start idle on initial cranking...

4) Oxygen sensor was way off, but that might be because my engine is running really rich??

It's supposed to be Idle-below 1V, Accel -.5-1V, Decel -0-.4V.

Mine idled at 29.6mV, I wasn't driving with DMM on, but I throttled the pedal Accel-22mV, Decel-26mV

This is odd, but it should not affect anything outside of slightly worse gas mileage...
It should see at least 0.5VDC at idle and decent acceleration.

6) Full range on the TPS is definitely off by a bit. It should read .8V at idle and mine sits at .54V. Can I get some feedback on that one? On the one hand off by .26V doesn't seem bad, BUT that is a significant amount when it's 1.4 of the total spec reading.

This might trigger one of those nasty E-OMP error codes which could trigger limp-home mode...


-Ted

[JustJeff]

^ I checked codes a while back and the only ones I had were for my solenoids from emissions delete and the AWS which my JDM does not have.

Although that is not entirely true. I pulled codes shortly after install and initial startup and had codes for every major sensor. After resetting the ECU they all disappeared..well other than the emissions and AWS.

I'm leaving now to reset idle, recheck TPS voltage, check timing, if time premits I'll backprobe my ECU and see if those readings are still the same.

As a general overview, I think I have some fundamental wiring issues going on. My AEM gauge will spontaneously show way over boost/vac. The last time it did it 5psi boost was the reference point during it's shutdown procedure. On startup and shutdown it will generally go to it's baseline then either dropdown and start operating, or shutdown. I didn't look when I first started up the engine but saw it while driving. When I turned the engine off the closing ceremony had it reference to 5psi.

Also my aftermarket alarm was so out of sorts that I disconnected the alarm cpu entirely. I didn't have constant power going to it at all and when I started disconnected negative wiring at the battery my alarm siren starts going off very faintly. Very strange in that the alarm should not have been getting any juice at all. When I reconnected the ground wire for the siren (connected directly to the battery sidepost) my siren starts going off full blast...again without having constant power to the alarm cpu.

Other oddities, my dome light is non-functional. The last time I checked voltage at my TPS I turned IGN to ON and did not get any ticking of the BAC for some time..then all the sudden it kicked on. Now I did have my ECU harness for TPS (IIRC the 2 harness) disconnected. Part of working today will be checking out whether having that harness disconnected replicates that same thing.

My wideband should be here tomorrow. Hoping to have it up and running this weekend. Maybe afr will shed some light on whatever is going on?

[RETed]

Originally Posted by JustJeff

check timing,

I think I forgot to address this, but...
Ignore the trailing mark for now.
I believe the trailing ignition timing is dependent on the boost sensor signal, so that's why it's not doing the proper 15-degree split.
As long as the leading is spot on...

As a general overview, I think I have some fundamental wiring issues going on. My AEM gauge will spontaneously show way over boost/vac. The last time it did it 5psi boost was the reference point during it's shutdown procedure. On startup and shutdown it will generally go to it's baseline then either dropdown and start operating, or shutdown. I didn't look when I first started up the engine but saw it while driving. When I turned the engine off the closing ceremony had it reference to 5psi.

This sounds like it's isolated to the aftermarket boost gauge itself?
If so, then it has nothing to do with your engine running problems...

Also my aftermarket alarm was so out of sorts that I disconnected the alarm cpu entirely. I didn't have constant power going to it at all and when I started disconnected negative wiring at the battery my alarm siren starts going off very faintly. Very strange in that the alarm should not have been getting any juice at all. When I reconnected the ground wire for the siren (connected directly to the battery sidepost) my siren starts going off full blast...again without having constant power to the alarm cpu.

This is a classic case of a ground loop circuit.
Like the above, this should not have anything to do with your engine running problems...

My wideband should be here tomorrow. Hoping to have it up and running this weekend. Maybe afr will shed some light on whatever is going on?

I doubt it.
I still have my money it's the TPS or related...


-Ted

[JustJeff]

Thanks for the feedback Ted,

Something very curious happened. I found my battery was nearly dead, and not enough to crank the car. Jumped it and was letting the engine warm up and the battery charge. After it got up to temp I starting setting the idle. It was sitting at just a nudge above 1k. When it had previously dropped down to barely idling and bouncing just above 0. I had been driving it like that for a week or so and after the engine warmed up idle would sit around 800ish. So I turned down the idle to just over 500. About this time my efan kicks on. I toggle my manual switch to have it run longer and bring the temps down further so my fan isn't kicking on and off while I'm working. I toggle the fan off after temps get down low enough and as soon as I do my idle drops from the 500rpm to just barely idling.


Also while the engine was warming up and the battery was charging my boost gauge was at 0psi rather than vacuum. It would go up from there if I toggled the throttle. When I turned the engine off closing ceremony took the boost gauge to almost 10psi.


I restart the engine, boost gauge is reading correctly at about 15in/hg but rpms are still amazingly low.


Can someone explain the difference between the two idle adjustment screws.

Fast Idle

[IMG][/IMG]


Not sure the name on this one, but man the pic sure captured the pollen on it (hood as been sitting up on it)



Fast idle is tied to thermowax and turning that screw does nothing for my idle. I am JDM with JDM BAC so I have no idle adjustment there. My only way of adjusting idle is the second pic...of which I do not know the name.

[vrracing]

I struggled with the idle setups on our JDM Tii.

I took the TB off to adjust the fast idle. I used a heat gun to test it. I put pictures and descriptions of what I did either on this or the other forum. The FSM is wrong.

The FSM talks about how to set the butterflies but nothing mapped to what was on the TB.

I used that big screw with the sleeve to set the idle. I used the two 12mm nuts on the throttle cable to ensure I had plenty of slack. IMO the engine should start and idle with the cable removed.

Don't forget the ISC. I grounded it straight to the negative terminal as I found that the bolt I was using under the main fuses wasn't working as a ground.

[JustJeff]

Originally Posted by vrracing

.

Don't forget the ISC. I grounded it straight to the negative terminal as I found that the bolt I was using under the main fuses wasn't working as a ground.

Is the ISC the same as the single green harness used to get CEL codes?

When checking timing I never jumpered anything. I simply got it warmed up, idling around 800ish and pionted a timing gun.

[Pete_89T2]

Originally Posted by JustJeff

I guess next up is to test AFM/MAF. One thing to note, I have a Cosmo AFM/MAF for a 13B. I'm assuming that could be a factor in the rich idle?

That could very well be the case, at idle and elsewhere in the power curve as the ECU uses the AFM as a primary input to manage FI. Is the Cosmo AFM a different part # than the original AFM that went with your ECU? I know AFMs are not interchangeable between S4 & S5 or T2 & NA's. I have no idea if the Cosmo AFM is interchangeable with anything else. What's the reason for using the Cosmo AFM, larger diameter opening/better flow?

Originally Posted by JustJeff

Is the ISC the same as the single green harness used to get CEL codes?

When checking timing I never jumpered anything. I simply got it warmed up, idling around 800ish and pionted a timing gun.

I think that's what he was referring to - the single terminal green connector by the battery that you ground when checking CEL codes, adjusting idle and timing. When grounded, the ECU inhibits the BAC from messing with idle speed, which you'll need to check/adjust idle or base timing.

[JustJeff]

Originally Posted by Pete_89T2

That could very well be the case, at idle and elsewhere in the power curve as the ECU uses the AFM as a primary input to manage FI. Is the Cosmo AFM a different part # than the original AFM that went with your ECU? I know AFMs are not interchangeable between S4 & S5 or T2 & NA's. I have no idea if the Cosmo AFM is interchangeable with anything else. What's the reason for using the Cosmo AFM, larger diameter opening/better flow?



I think that's what he was referring to - the single terminal green connector by the battery that you ground when checking CEL codes, adjusting idle and timing. When grounded, the ECU inhibits the BAC from messing with idle speed, which you'll need to check/adjust idle or base timing.

I ended up with the Cosmo AFM by accident and many years ago. My original turbo swap was done by a shop in Indy, AIM Tuning. While getting parts together for the swap I bought off eBay what I was told was an turbo RX7 AFM. I didn't know any different till many months later when the swap was completed. By then I couldn't go back to the seller so I used it. I've been using it since oh...about 2008 or so. No issues...well till now :P

At one time you could read the part # and that's how I verified it's a Cosmo, but now that sticker has been worn down quite a bit.

Thanks for the heads up on jumpering that, this is the first I've read about it.

[RETed]

Originally Posted by JustJeff

Something very curious happened. I found my battery was nearly dead, and not enough to crank the car. Jumped it and was letting the engine warm up and the battery charge. After it got up to temp I starting setting the idle. It was sitting at just a nudge above 1k. When it had previously dropped down to barely idling and bouncing just above 0. I had been driving it like that for a week or so and after the engine warmed up idle would sit around 800ish. So I turned down the idle to just over 500. About this time my efan kicks on. I toggle my manual switch to have it run longer and bring the temps down further so my fan isn't kicking on and off while I'm working. I toggle the fan off after temps get down low enough and as soon as I do my idle drops from the 500rpm to just barely idling.

When you get engine idling / running problems dependent on coolant temp, this implies the coolant temperature sensor could be the cause...
Does it check out?

Also while the engine was warming up and the battery was charging my boost gauge was at 0psi rather than vacuum. It would go up from there if I toggled the throttle. When I turned the engine off closing ceremony took the boost gauge to almost 10psi.

You talking strictly about the aftermarket boost gauge, right?
I think the aftermarket boost gauge is defective.

I restart the engine, boost gauge is reading correctly at about 15in/hg but rpms are still amazingly low.

Not possible - see above.

Can someone explain the difference between the two idle adjustment screws.

Fast Idle

Not sure the name on this one, but man the pic sure captured the pollen on it (hood as been sitting up on it)

Fast idle is tied to thermowax and turning that screw does nothing for my idle. I am JDM with JDM BAC so I have no idle adjustment there. My only way of adjusting idle is the second pic...of which I do not know the name.

In the first picture, the idle adjust screw is at the very top, middle of the pic.
I believe it's the same pic as the screw on the left in the 2nd pic?
The screw should be toward the rear of the engine, closer to the firewall.
The screw should be pointing toward to the passenger (US-spec) fender; you need to lean over the passenger fender to adjust this screw.

Don't mess with the "Fast Idle" screw, as this just adjusts the double throttle plates relative to each other - yes, it should not affect idle (that much).

This is still a stock TB, right?
No removal of the double throttle plates?


-Ted

[JustJeff]

Originally Posted by RETed

When you get engine idling / running problems dependent on coolant temp, this implies the coolant temperature sensor could be the cause...
Does it check out?

It did at the ECU pin anyway.
FSM specs for 2E:
idle cold: .4-1.8v
water temp 68: approx 2.4v

Mine was
idle cold: .532v
water temp 58: 2.357v

Originally Posted by RETed

You talking strictly about the aftermarket boost gauge, right?
I think the aftermarket boost gauge is defective.

Gauge is practically brand new AEM gauge. It mostly seems dead on, but every so often it bugs out and reads over. The manual that came with it broke down the voltage it sees in relations to boost the sender sees. When it is bugged out often times turning off the engine and restarting it corrects the issue.

Originally Posted by RETed

In the first picture, the idle adjust screw is at the very top, middle of the pic.
I believe it's the same pic as the screw on the left in the 2nd pic?
The screw should be toward the rear of the engine, closer to the firewall.
The screw should be pointing toward to the passenger (US-spec) fender; you need to lean over the passenger fender to adjust this screw.

Don't mess with the "Fast Idle" screw, as this just adjusts the double throttle plates relative to each other - yes, it should not affect idle (that much).

This is still a stock TB, right?
No removal of the double throttle plates?


-Ted

It's a stock JDM TB. It has double throttle plates. I just starting rebuilding a USDM TB that I'm going to put on once it's cleaned and adjusted.

[RETed]

Originally Posted by JustJeff

Gauge is practically brand new AEM gauge. It mostly seems dead on, but every so often it bugs out and reads over. The manual that came with it broke down the voltage it sees in relations to boost the sender sees. When it is bugged out often times turning off the engine and restarting it corrects the issue.

I have a Trust / GReddy EGT gauge that basically does the same thing.
I'm too lazy to redo and trouble-shoot the whole thing, but it works most of the time.
The aftermarket gauge has it's own dedicated sensor and wiring, right?


-Ted

[JustJeff]

^ Yeah I remember you posting about your TB and I found the thread on the other forum about rebuilding them. I'm in the process of tearing down a spare USDM S5 turbo TB. I was actually going to work on it, but then found I was out of gas for my disposable torch.

So the fast idle is for when the engine is still warming up? Adjusting my fast idle does nothing. The sleaved idle is what I should be (and have been using to set idle).

ISC? Not familiar with that abreviation. I went through my grounds, or all of them I could think of and find. I did the grounding mod at the ECU. I cleaned up all the grounds down to clean metal. I've got the engine grounded on top of the keg to the firewall. I checked the engine harness ground that is on top of the engine keg. I have common grounds for gauges and headunit at the shifter bracket. I have another common ground at the driver kick panel. I went through my grounds for my stereo's amps. IIRC I got the one at the driver shock tower. I even got the one under the trailing coil. Right now my fan and alarm siren are grounded directly to the battery. Then I have an additional battery neg terminal to body chassis ground.

[JustJeff]

Overall I think I have wiring issues. I certainly have one for the aftermarket alarm, the boost gauge is certainly buggy.

Maybe that faulty wiring extends from accessories to actually affecting engine performance? I don't know quite yet.

[RETed]

Originally Posted by JustJeff

Overall I think I have wiring issues. I certainly have one for the aftermarket alarm, the boost gauge is certainly buggy.

Maybe that faulty wiring extends from accessories to actually affecting engine performance? I don't know quite yet.

None of the above is tapped into the "EM" (Engine Main) electrical harness, right?


-Ted