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Discussion Starter #21
So my observations on trying to adjust it is this: the TPS requires roughly 100 degrees of throw to go from 0-100% and my throttle body only has 90 degrees of throw for the sensor. Im used to these sensors having a pretty big dead zone before they start to read, and this one barely has any. What are your guys’ thoughts on this? Should I try a new sensor? Is there a sensor better suited to work with an aftermarket TB?
 

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Discussion Starter #22
Ok so I looked into this a little more. tps calibration is not dependent on the ecu % range, From what I read is that true 0% and 100% is read at 0v and 5v respectively. The specs to set the tps on our cars are roughly .5v closed, and 4.5v wot. Thus the ecu should never see 0 or 100, but a more of a range between 10-90%. And most cars are set to throw a cel code for the tps if volts or percentages outside of this range are seen for extended periods of time. So my tps is actually reading correctly.

Time to just get the damned thing tuned already. lol. Anyone know where to get a p28 chipped ecu ready to tune at? I’d do it myself but I don’t trust myself to solder shit to a circuit board just yet
 

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if you had one or the other concerning the skunk2 intake manifold, or the camshaft you would be fine most likely.

However, if you have a sticky fuel injector, or even one of the enrichment sensors acting poorly, this would indicate the need to investigate.

enrichment sensors generally mean the temp or pressure sensors, aka, coolant temp, air temp, MAP, etc..


Check with a scanner that reads live data, and see if you can find a fellow civic or integra owner who wants to share info on a nearly stock system if possible.


For now, you could install a stock throttlebody to help deal with partial throttle and low-mid rpm driving. If the issue clears itself up noticably, that tune you are talking about mightneed to happen sooner rather than later.
 

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if you had one or the other concerning the skunk2 intake manifold, or the camshaft you would be fine most likely.

However, if you have a sticky fuel injector, or even one of the enrichment sensors acting poorly, this would indicate the need to investigate.

enrichment sensors generally mean the temp or pressure sensors, aka, coolant temp, air temp, MAP, etc..


Check with a scanner that reads live data, and see if you can find a fellow civic or integra owner who wants to share info on a nearly stock system if possible.


For now, you could install a stock throttlebody to help deal with partial throttle and low-mid rpm driving. If the issue clears itself up noticably, that tune you are talking about mightneed to happen sooner rather than later.
Well I’ve pretty much ruled out all my sensors at this point. I voltage checked the map and iat sensors already, they’re operating within normal parameters. The coolant sensor checked out good as well as the tps.

Getting my hands on a stock tb probably isn't worth it at this point. My original won’t work with my set up anymore because it’s a auto-manual swap. I switched it and the manifold out when I did the ecu and iacv rewire. I’m just gonna have it tuned asap.

I wouldn’t even have the cam in it, but the machine shop I had do the head dropped the damn cam and broke one of the ends that the distributor mates with. So at least I got a free stage 1 out of that. Lol

I did unplug the upstream 02 sensor today and drove it a little after messing with the tps. That seemed to really clear it up quite a bit. It definitely richened up my a/f ratio in the low end some. So I’ll just run it open loop until I can get it tuned.

Thanks to everyone who posted and gave me ideas on what to check. Special thanks drtalon123 for all the info. I can rebuild one of these things with my eyes closed, but chasing electrical ghosts is not my forte. I learned a few things that hopefully I can use to help someone else out in the future.
 

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Ok so I looked into this a little more. tps calibration is not dependent on the ecu % range, From what I read is that true 0% and 100% is read at 0v and 5v respectively. The specs to set the tps on our cars are roughly .5v closed, and 4.5v wot. Thus the ecu should never see 0 or 100, but a more of a range between 10-90%. And most cars are set to throw a cel code for the tps if volts or percentages outside of this range are seen for extended periods of time. So my tps is actually reading correctly.

Time to just get the damned thing tuned already. lol. Anyone know where to get a p28 chipped ecu ready to tune at? I’d do it myself but I don’t trust myself to solder shit to a circuit board just yet
You have me curious about this now haha. I have my old OBD2 D16Y8 ECU laying around, I'm gonna power it up on the bench and wire in a TPS sensor, then use my ELM327 device directly at the ECU to read global OBD2 data from it and watch the generic TPS parameter.

You are correct about 0% being roughly 0.5v and 100% being approx. 4.5v, and anything beyond those voltage ranges could fall into the circuit fault range and fault codes will set. Honda knows this as well, as they designed their system. Because they are the ones that know how this works, they have to make sure the "interpreted TPS percentage" gets mapped to the global OBD2 standard PID in the same way as Honda's proprietary PID.

Typically, Global OBD2 data reporting standards in the US are pretty hardcore about making sure OEMs map their proprietary value counterparts everywhere they are required. The mandates usually require OEMs to provide global OBD2 data to exactly match the proprietary data items, especially when it comes to ANY component that can affect emissions (TPS is an emissions affecting electronic component, and must be reported accurately according to the standards).

Global OBD2 mandates that 0% TPS shown on a Honda OEM service tool hooked to your car should still show 0% on a generic OBD2 scanner. It is the OEM's responsibility to make sure these global parameters are reported correctly, otherwise they couldn't sell their cars as this global data is part of emissions requirements of CARB and EPA.

All of the global OBD2 stuff falls into many laws, such as the right to repair law, and all of the federal/California emissions reporting laws.

The government basically said to every car OEM around 1992:

Government: "In 1996, I don't want to have to buy 30 different scan tools from all you guys to read data from each different car. I want X # of data parameters available to be read with 1 TOOL across EVERY car that wishes to be sold in the USA. I need this data so that the playing field is level, and we can have insight into how everyone's cars basically work from an emissions perspective, without needing to go through the trouble of consulting with 10,000 different engineers at 300 different companies to make sense of it all. If everyone implements the data this way, we won't have a problem."


All car OEMs: "Yes Lord USA, anything you wish.... (mumbles and groans)..."
 

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So my observations on trying to adjust it is this: the TPS requires roughly 100 degrees of throw to go from 0-100% and my throttle body only has 90 degrees of throw for the sensor. Im used to these sensors having a pretty big dead zone before they start to read, and this one barely has any. What are your guys’ thoughts on this? Should I try a new sensor? Is there a sensor better suited to work with an aftermarket TB?
That is weird, every TB in existence that uses a butterfly valve can only utilize the range of 90 degrees fully opened to closed lol. It would be weird to build a sensor that doesn't conform to that.

Something doesn't sound right (either TB or sensor) if you can't get the sensor to read close to 0%. 10%+ is definitely too much to be your closed value. I'm curious if voltage output is at or very close to 0.5v when that thing is reading 10% on the service tool :)

Because of that thought, one more thing I could suggest to try at this point: I wonder if maybe there is a stored 0% point that happens during an initial Key On Engine Off. Have you tried disconnecting the battery for 10+ minutes, installing the sensor within range, then reconnecting the battery and seeing what happens, to see if your 0% comes back? Again, just shooting ideas out there :)

When I get my OBD2 D16Y8 ECU hooked up on the bench, I'll report back and let you know what the min TPS percentage indicated on global OBD2 was!
 

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On properly working sensors and adjustment, 0% is never seeen.

Generally, the range is around 3-4% to 95% or so, it varies.

But you will never seen 0% and 100%
 

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Discussion Starter #29
So my observations on trying to adjust it is this: the TPS requires roughly 100 degrees of throw to go from 0-100% and my throttle body only has 90 degrees of throw for the sensor. Im used to these sensors having a pretty big dead zone before they start to read, and this one barely has any. What are your guys’ thoughts on this? Should I try a new sensor? Is there a sensor better suited to work with an aftermarket TB?
That is weird, every TB in existence that uses a butterfly valve can only utilize the range of 90 degrees fully opened to closed lol. It would be weird to build a sensor that doesn't conform to that.

Something doesn't sound right (either TB or sensor) if you can't get the sensor to read close to 0%. 10%+ is definitely too much to be your closed value. I'm curious if voltage output is at or very close to 0.5v when that thing is reading 10% on the service tool <img src="http://www.d-series.org/forums/images/smilie/icon_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />

Because of that thought, one more thing I could suggest to try at this point: I wonder if maybe there is a stored 0% point that happens during an initial Key On Engine Off. Have you tried disconnecting the battery for 10+ minutes, installing the sensor within range, then reconnecting the battery and seeing what happens, to see if your 0% comes back? Again, just shooting ideas out there <img src="http://www.d-series.org/forums/images/smilie/icon_smile.gif" border="0" alt="" title="Smile" class="inlineimg" />

When I get my OBD2 D16Y8 ECU hooked up on the bench, I'll report back and let you know what the min TPS percentage indicated on global OBD2 was!
Yeah let me know what ya find out. But the way I figure it, the operating range of the tps % is between 10-90%. This will vary slightly from car to car, especially with different manufacturers. But being that our tps’ are set from .5v-4.5v, on a 0-5v system, The “dead zone” that the ecu should never see is about 10% in either direction. Every .5v on a 5v system equals 10% so the math adds up in favor of this being right. In fact when I had the tps removed from the Tb the ecu threw a low tps voltage code when it was reading 0%.

I set mine back by voltage. .5v closed, 4.5v wot and checked the ecu again. It’s showing me a range from 10.2% - 89.9%. But one thing we have to remember that the ecu is programmed to read from .5-4.5v, not 0-5v and not percentages. It recognizes .5 as fully closed and 4.5 as wot. So I don’t think that the % points matter all too much to the ecu.


Oh and I’m still driving the car in open loop after unplugging the upstream o2 sensor. It’s definitely leveled out my a/f ratio. I’m not running as lean at low throttle, or as rich at high throttle. It’s a lot easier to drive like this. No more breaking up at low rpm, but still a little sluggish. But I’ll take sluggish over breaking up any day. But I’m working on getting a s300 and p28 so I can get a tune. Only if I could just stop getting out bid on the ecu. These things are damn near worth their weight in gold anymore. Lol
 

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Lucky bastard. Lmao. If only we could tune the obd2 like the obd1, then I’d be set. I’ve got 3 p2p ecu’s. 2 manual 1 auto. I really need to try n sell the spares but nobody’s needs one unless theirs takes a shit.

How easy is it to install a s300 onto one of these ecu’s? As it stands it’s already gonna cost almost $700 for the ecu and chipping kit. I’d rather not have to pay another 100-200 for someone to install it. Lol

So I guess I should order my new exhaust before I go and get it tuned too. Would be pointless to get it tuned then swap the exhaust. 🤣 I’m tired of my shit rattling lmao
 
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