Possible Throttle Position Sensor (TPS) issue

[steveplant123]

Hi there all,
Does this sound familiar?
I was riding along fine when suddenly the NT turns into a bucking bronco of a ride – dies/surge/dies/surge/dies/surge (on 1 to 2 second ‘loop’) and then dies completely when I pulled over. NOT good in city traffic! Started her up again and she was fine.

I have been having this issue sporadically over the past 3,000 miles however the ‘FI’ (MIL) light has never come on to indicate any fault condition and the only error code I have been able to retrieve (see the Haynes Manual) is ‘01’ – an MAP sensor error – which doesn’t really seem to match my symptoms.

After reading lots of posts regarding the spark plug caps issues I replaced them and for good measure I changed the plug leads for silicone items as well.

I have also pulled every plug and socket I can find to clean the contacts and added a smear of di-electric grease to eliminate any poor contact issues.

However, after a few months, the bucking bronco has reared its ugly head again!

My gut feeling is that this is an intermittent fault with the throttle position sensor (TPS)

There seem to be a lot of posts about this ranging from ‘replace the whole throttle body’ (at stupid money!) to replacing the actual culprit, ie the JT7H sensor unit itself!

Now my big question is……. Has anyone done this successfully?

It would seem to me that a JT7H is, well, just a JT7H! (as fitted to many Honda cars and these appear to available from around £15 upwards) but am I wrong? Do those digits AFTER the ‘JT7H’ really signify anything of importance?
(I believe the full code for the NT700 is JT7H 40819)

Intriguingly the suggested Yamaha alternative – ISL 85 885 –00 ($33.36 on Amazon!) appears to be a JT7H with ‘40819’ stamped on the casing

The Haynes manual has a dire warning about dismantling the throttle body components and I appreciate that if the sensor were to be replaced it would have to be adjusted (on its slotted holes) to give the correct voltages at fully open and closed throttle positions.
I am not 100% sure, but I assume this is what is meant by ‘calibration’

One post also mentioned that an after market replacement TPS had its location slot in the wrong orientation to engage with the throttle body shaft. Any thoughts?

In conclusion it seems to me that there is a lot of humbug around regarding sensors (car or motorcycle) If the Manufactures can make the sensor (apparently!) specific to one model they can charge a LOT more for what in fact is a fairly generic sensor.

Any comments, observations or experiences would be welcome before my winter ‘tear down’ to address this issue and others (tappet adjustments anyone!!!)
Thanks in advance for your time, Steve P
(2008, NT700VA, 9000 ‘dry’miles from new)

 

[ARKNT]

Engine "Hunting" any ideas to the cause? | Maintenance

I have a problem with my 2010 Deauville NT700VAA. She has about 130,000 miles on the clock and about 200 miles ago the engine started "hunting" at certain revs and engine temperature. The revs are usually between 2,000 and 3,500 and the engine temperature at approximately the quarter mark...

www.nt-owners.org

You might review this thread for calibrating TPS.
Also your 2008 NT may be slightly different from the USA versions that are 2010 & 2011.

Sounds like you have tried to clean up the electrical connections which could be a possibility, have you done any measuring on the TPS itself? Intermittent problems can be difficult to find & fix.

Arknt

 

[rc_heli_nut]

I would clear the code, and look for the MAP sensor code to possibly return. If it does, replace the MAP sensor. Carefully check the vacuum hoses, any leading to the MAP. I would not replace the TPS sensor without first ruling out a problem with MAP.

 

[NewTo700V]

Hi there all,
Does this sound familiar?
I was riding along fine when suddenly the NT turns into a bucking bronco of a ride – dies/surge/dies/surge/dies/surge (on 1 to 2 second ‘loop’) and then dies completely when I pulled over. NOT good in city traffic! Started her up again and she was fine.

I have been having this issue sporadically over the past 3,000 miles however the ‘FI’ (MIL) light has never come on to indicate any fault condition and the only error code I have been able to retrieve (see the Haynes Manual) is ‘01’ – an MAP sensor error – which doesn’t really seem to match my symptoms.

After reading lots of posts regarding the spark plug caps issues I replaced them and for good measure I changed the plug leads for silicone items as well.

I have also pulled every plug and socket I can find to clean the contacts and added a smear of di-electric grease to eliminate any poor contact issues.

However, after a few months, the bucking bronco has reared its ugly head again!

My gut feeling is that this is an intermittent fault with the throttle position sensor (TPS)

There seem to be a lot of posts about this ranging from ‘replace the whole throttle body’ (at stupid money!) to replacing the actual culprit, ie the JT7H sensor unit itself!

Now my big question is……. Has anyone done this successfully?

It would seem to me that a JT7H is, well, just a JT7H! (as fitted to many Honda cars and these appear to available from around £15 upwards) but am I wrong? Do those digits AFTER the ‘JT7H’ really signify anything of importance?
(I believe the full code for the NT700 is JT7H 40819)

Intriguingly the suggested Yamaha alternative – ISL 85 885 –00 ($33.36 on Amazon!) appears to be a JT7H with ‘40819’ stamped on the casing

The Haynes manual has a dire warning about dismantling the throttle body components and I appreciate that if the sensor were to be replaced it would have to be adjusted (on its slotted holes) to give the correct voltages at fully open and closed throttle positions.
I am not 100% sure, but I assume this is what is meant by ‘calibration’

One post also mentioned that an after market replacement TPS had its location slot in the wrong orientation to engage with the throttle body shaft. Any thoughts?

In conclusion it seems to me that there is a lot of humbug around regarding sensors (car or motorcycle) If the Manufactures can make the sensor (apparently!) specific to one model they can charge a LOT more for what in fact is a fairly generic sensor.

Any comments, observations or experiences would be welcome before my winter ‘tear down’ to address this issue and others (tappet adjustments anyone!!!)
Thanks in advance for your time, Steve P
(2008, NT700VA, 9000 ‘dry’miles from new)

Before you load up the parts cannon, please read my post (#131) in this thread and then follow the subsequent posts until the topic's end. Pay particular attention to post #140.

Throttle Position Sensor TPS Part Number | Electrical

Hi Clement, I have had MIL 8 issues for over 2 years. My story is well documented in this thread. I replaced the TPS sensor, the MAP sensor, the battery, and the voltage regulator, and even tried different gas because others have had success with one or more of those attempts in the past. I do...

www.nt-owners.org

 

[dnktng]

Here is my MAP sensor fault from 2013.

I was only reading a MIL code 1, like yours. It was causing a bucking bronco, like yours.

I have a detailed history of trying to solve the code. Here was my entry describing the bucking bronco:

Past 6 engine start ups, engine started fine but would hesitate, jerk, and sometimes stall just above idle until engine warm for ~10 minutes. Pulled ECM and cleaned.

Here's the entry trying to fix the hesitations, jerking and MIL code 1.

As part of 24K maintenance:
-Changed spark plugs. Found rear plug with possible fouling (moderate darker dusting than front plug (and past plugs) with small peaks and some craters.
-Inspected Spark plug caps & wiring. Good
-Found possible indication of air leakage between rear throttle body and insulator. Cleaned area & reseated throttle body.
-Disconnected , inspected, air blasted, reconnected 11 connectors (MAP, IACV, Both Injectors, Fuel pump, Throttle Position, Cam Position, Inlet Air Temp, )combined 10 wire connector to MAP, TP, IACV, CMP, Purge Control, Pair Solenoid). No conclusive connector problems found, but some felt weakly connected.
-Relieved stress on IAT wires from harness by cutting back tape.
-Disconnected & reconnected the 4 connected attached to left middle cowl ( Ign Switch, Right Handlebar, Left Handlebar 4P, Left Handlebar 6P).
-Inspected vacuum tubing, fuel lines, wiring harnesses for damage. Straightened/corrected Throttle body vacuum line routing....not suspected of causing any problems.
Rode 10 miles, hesitation & stalling & general poor running has cleared. Found ECM Code 1 stored (expected, from prior to starting maintenance), reset ECM codes.

The bold items are what I think were the culprits... and either could have caused an intermittent MIL code 1. This fixed the problem and it has not returned in 9 years. So if I was to list the 3 most likely causes today it would be:
1. Large 10 pin connector to the MAP, TPS, IACV, CMP, Purge Control, and Pair solenoid being loose and not fully seated. Its under a square frame support to the left of the throttle bodies. Its called a throttle body sub harness connector. Round and grey.
2. MAP Connector at the MAP sensor.
3. Air leakage into the rear cylinder air intake caused by the throttle body not fully pushed into the rubber insulator.

 

[steveplant123]

Engine "Hunting" any ideas to the cause? | Maintenance

I have a problem with my 2010 Deauville NT700VAA. She has about 130,000 miles on the clock and about 200 miles ago the engine started "hunting" at certain revs and engine temperature. The revs are usually between 2,000 and 3,500 and the engine temperature at approximately the quarter mark...

www.nt-owners.org

You might review this thread for calibrating TPS.
Also your 2008 NT may be slightly different from the USA versions that are 2010 & 2011.

Sounds like you have tried to clean up the electrical connections which could be a possibility, have you done any measuring on the TPS itself? Intermittent problems can be difficult to find & fix.

Arknt

Thanks for your response. Not yet stripped it down to investigate fully but I will try your suggestion of calibration first. Yes, I agree Intermittent electrical gremlins are a real pain to pin down!

 

[steveplant123]

I would clear the code, and look for the MAP sensor code to possibly return. If it does, replace the MAP sensor. Carefully check the vacuum hoses, any leading to the MAP. I would not replace the TPS sensor without first ruling out a problem with MAP.

Thanks for your response. Not yet stripped it down to investigate fully but I will try your very helpful suggestions

 

[JQL]

It sounds like TPS (DAMHIK). It is very easy to re-calibrate the TPS. (Red and Yellow wire on the Grey ECU plug and Green and Orange wire on the Black ECU plug, use needles in the connectors, and set to as close to >=4.00V as you can, the lower the better - I found anything between 4.00V and 4.10V seems to work OK)

The only problem is the TPS is attached with TORX bolts and there is zero space to get anything with a handle in there. So, get a TORX bit (25) and clamp it in some Mole Grips (Vice Grips). You can then loosen (and later tighten) the bolts.

I'm in the process of doing a video about my experience calibrating my TPS, so if you can wait a few days (after the weekend) I'll have it ready. In the meantime, I discuss my TPS problem and give some very basic info in this video: Swan Song (Sort of)

 

[dnktng]

It sounds like TPS

If the TPS is intermittently failing it should have given an intermittent Code 8 at least once. He reported only getting Code 1 for the MAP sensor.

NewToNT700v reported getting both code 1 and 8 and suspects that his fix was the 10 pin connector the contains wiring for both the MAP sensor and TPS. I reported only having only a code 1 with similar bucking bronco symptoms (like StevePlant123) and suspect that my fix was the 10 pin connector that contains wiring for MAP sensor.

TPS fail... sure. But when the ECM is saying MAP sensor is failing and that the TPS is not, it would be cheaper, easier and makes sense to resolve the MAP sensor and/or the MAP sensor wiring problems before replacing or adjusting a component that no symptom directly points to.

however the ‘FI’ (MIL) light has never come on to indicate any fault condition and the only error code I have been able to retrieve (see the Haynes Manual) is ‘01’ – an MAP sensor error – which doesn’t really seem to match my symptoms.

It's quite possible that the FI/MIL light is toggling in and out as the fault appears and disappears rapidly, not giving a real chance to see it. The only way to know is to view the stored codes in the ECM. Clear the ECM codes in the ECM and see if the MAP code 1 reappears.

I believe a MAP sensor failure will put the ECM in limp mode, just like a TPS failure code would. What I recall was a rather violent loss of power following by a rapid restoration of power... think engine off/engine on type of herky jerking without seeing any code. But a fresh Code 1 was always in the ECM. The NT was controllable in a straight line while bucking, but if it ever happened in a corner the results may have varied drastically.

 

[JQL]

It only takes a minute or so to insert two needles into the ECU connectors and measure the TPS voltage. I would do that as a matter of course. You've lost nothing, but, possibly, eliminated or found a cause...

 

[steveplant123]

Hi there all once again and many thanks for your help with my ‘bucking bronco’.
I would tend to agree that the most likely cause of my problem is a poor contact rather than a failed sensor. (TPS or MAP, as they are both on the same harness)

With this in mind I have located the multi-connector for the sensors ‘sub- harness’.
(It is well hidden and I missed it on my first check through of all the connectors.)
So I will give it a really good clean up with contact cleaner and I will let you know how I get on.
Of course intermittent faults are just that – intermittent! So its difficult to know if you have fixed it or not!!!

If the fault reoccurs I will change the throttle position sensor but first I have a question……

I can see its is a‘JT7H’ (which seems to be common to many Honda vehicles)

But this is followed by ‘80129’

Are these digits important or just manufacturing codes?

Has anyone replaced the sensor and if so what did you use?

Did you get an exact match for the full code - : ie JT7H 80129

Is this specified for any other vehicles? (to use to get a match for the NT700)

Hope someone can enlighten me before I buy the wrong $20 part!!!!
Cheers for now, Steve P

 

[ARKNT]

Throttle Position Sensor TPS Part Number | Electrical

FYI Throttle Position Sensor (TPS). Honda call it integrated. I have just discovered why.. Honda cycle parts have MEW part numbers. The TPS is a JT7H a quick ebay search will tell you this is a TPS for a 03-05 Honda Accord Element 2.4L and some others. This not a Honda motorcycle part. I have...

www.nt-owners.org

You might review the above thread for part number info. It may help but may confuse things also.
I would also inspect for vacuum leaks and such as others have said before ordering/replacing parts.

Good luck
Arknt

edit: I just noticed this thread has already been suggested.