JW racing

I wondered if anyone else is having similar TPS issues.I have been having an ongoing issue with TPS sensors failing on me in my K20R powered race car and I want to get to the bottom of it and fix it, or find a way to use a different TPS with a fabricated adapter.

I thought I may have a wiring issue,so I basically replaced every harness on the car with a brand new one.I realized that was not it after the failures continued.I thought it may be the brand of sensor,oem or not.That came to no result either.So the last few sensors, I opened it up to discover the problem,small internal wire gauge breaking/failing.Is it vibration,maybe heat?

In the pictures are a OEM Keihin B series TPS :note the lage diameter internal wire similar to the actual plug prong size.
Then note the "aftermaket brand" K series TPS: It has very tiny wire size that seems far too fragile to be on a vehicle.(Tack for size comparison.)
Note the OEM K series Keihin TPS on bottom: Direct connect to the ceramic board and a very durable design,the fragile board sucks though! Large wire like B series and durable but the Keihin downfall is the ceramic board sometimes breaks on them, and I can't find one without buying a whole TB.Anyone have one

Since I am using aftermaket all the time,This wire is what is breaking on my sensors consistantly.The car runs awesome,then randomly shuts off and goes into limp mode 20mph or 2000rpm.I replace the sensor,recal the Kpro and the car runs again till the sensor randomly fails the next time.Another issue is a certain aftermarket brand uses keihin housings and they are not the same as the real OEM ones as they have the wire inside.

integrawow

These are some assumptions that you may have already thought of. Hopefully it will be of help.

First, just in case its some sort of an electrical crisis, and if you have the tools to do it, check amp loads on the fail prone circuit. See what kind of electrical load it is seeing. It may even simply be an intermittent problem such that it will intermittently short out. This could bring up an issue with a reference voltage that is too high.

Then ultimately compare this electrical load to that of a stock Honda k powered car. In doing this, you take KPRO out of the equation.

onefstek

I know you can buy the a3 tps sensor from honda but not the a2. They turn oposite, so you can't use it, but you might be able to use the circuit board from the a3 on the a2 sensor.

Ill see if I have a broken a3 and a2 sensors to compare to one another.

Stefan

JW racing

Thanks guys,
Good tips integrawow, I have left the kpro for last hoping it is not the issue, and actually want to have it inspected by Hondata. It's own datalogger does not pick anything up that is abnormal as far as I can tell,when the sensor goes bad,the graph looks like a seismograph.With a voltmeter I have tested the suspect circuit in the harness quite a few times and it actualy is right inline with the old engine and chassis wire harnesses I have replaced.

Well the best sensor is original,it is a keihin brand.Though they have a fragile ceramic board they are rare to break and as you see by the pictures the internal wiring is fool proof.I have not had the pleasure of being able to use a real OEM sensor to compare in racing,since I bought my engine it had the broken sensor.I hope to find access to a few good used ones or that Honda sells them sometime without buying a Complete new TB for 450 bucks.The aftermarket sensor in the middle shot was actually housed in a keihin housing so I thought I got a good "OEM style" sensor,but was fooled.I am not the only one aparently.I don't want to put these companies names out there but all of these sensors should be built better.A "warranty" helps but is just a mask for the problem.I have had about 4 sensors replaced by one company at no charge,yet each sensor is a different design and a fragile item of failure.It needs to be thick wire internally like the B series and K series OEM sensors pictured,yet have a old fashined durable green fiberglass circuit board and this issue will be solved.

The conclusions I have come to is, the "aftermarket" sensors I have been getting (middle shot) are no match for my needs in road racing or even many street cars,and should be redesigned. If I can find one,I need the beefy OEM Type-S(lower shot) and I will be fine as long as I dont break the ceramic board..

I would like to see if anyone out there has a broken TPS to open and show us the insides to compare brands.

JW racing

I was reluctant to do this because I didnt want to put any companies on blast.But I just came back from the garage and here you go,this picture is a BLOX TPS,you can see it is in everyway identical to the OMNI sensor in the center pic of the first post.Maybe a tad better as it has thicker gauge on the contact wires and actually a better contact on the rotating wheel as well.Still failed as you can see and by no means the beefy curved metal like OEM has on the bottom in the first post.

The only way to cure this problem is to make them like OEM HONDA keihin.
DO NOT be fooled by a company's sensor housing being Keihin,these are still not the same as the factory sensors.Honda needs to sell these seperate and they will make a ton of money.

BLOX,OMNI,BWR = Same cheap mass produced sensors,different sales person.

7rrivera7

iTrader: (1)

Looks like you have a voltage issue - look at the discoloration on the edge of the wires near the solder pad...

JW racing

The engine to ecu harness, old and brand new,have both checked out inline with a stock rsx-s, 5v feeding the sensor,also reads.45 closed and 5v open with key on. Car runs great, sensor randomly fails, can be one month or can be one hour.Nothing on the datalogger and no codes either.
I have not run a real oem Tps sensor to see if that holds up,these all are aftermarket that are failing.

Tyson

interesting difference between OEM and those sold as "identical".

can you forget the wires? are they resistor sensitive? if not, drill holes thru the contacts in the white board. then solder a post thru each contact.

but i still think you can drill a small hole in the housing, fill with epoxy and that will greatly help it.

howd you kill your first OEM TPS? [nevermind: since I bought my engine it had the broken sensor]


oh and ... obligatory Omni FAIL. lol.

Tyson

those arent very sophisticated looking solder joints either. i wonder if its a soldering issue itself.

JW racing

I have a real Type-S OEM TPS now and it has been fine at the Dyno,we shall see at the first race how it will hold under those conditions.

RagingAngel

seems to me that your radiator is still causing the issue of sorts...well the heat radiating from it.

but it's likely that it's the combination from the radiating heat and the inherent vibration of your car going 8000rpm that's causing that frail little piece of solder to just break off and die....

BolivianFuego

Interesting! So there hasnt been a for sure reason why TPS's go bad?

I had a K20R swap in EG. It wasnt just a street/weekend racer on the drag strip. One day I was throwing codes and turns out the TPS was messed up. I found one for sale a while back, replaced it, but never drove the car much, shortly after, i sold it.

I still have no idea why it just randomly broke. It was when i first installed the RBC manifold when they were just being released. I thought by me mishandling the TB that maybe it knocked and broke somewhere, as i hear TPSs were really gentle, or that maybe the vibration could have broken it.

Either way, I still dont know waht caused it! In for an answer! LOL And for the future for when i do this swap again!