Sunday, November 14, 2010 - 05:52 pm, by: Frank Csapo(264ttr)
Hi everyone,
I am trying to chase up some issues with my 1JZ conversion as it's still using far too much fuel (220km from 45L). I ran the diagnostic mode and received DTC 42 - No 1. Vehicle Speed Sensor Signal (4 blinks, pause, 2 blinks) as determined from this thread: http://soarercentral.com/sc-forum/messages/1113/862.html?1100787369
I am running an A/T ECU with a manual R154 gearbox. I am not running the Toyota speed sensor, my speedo cable is mechanical and goes straight from the pickup in the gearbox to the back of my speedo. According to the diagnostic detection conditions, it states that DTC 42 will come up if all of the following conditions are met: a) No.1 vehicle speed signal: 0km/h b) Engine speed: 2,800RPM or more c) Park/neutral position switch (PNP): OFF
This code is coming up with the engine off. I have pulled the EFI fuse to try to clear the code, but it comes back when I test it again. I can understand conditions A and C to be met, since I have no sensor, and my PNP has been bridged to allow the engine to start, but what could be causing my car to think it's revving over 2,800RPM while switched off? ...Or am I barking up the wrong tree with this logic?
I am receiving no other codes, just this one. If anyone can help, it'd be appreciated!
Wednesday, November 17, 2010 - 01:53 am, by: Frank Csapo(264ttr)
I did a search, and it appears that the R154 can be fitted with an electric speed sensor, but it's only good for an electric speedo. My speedo is mechanical so it would work for me, and there is no way to run both.
What about it thinking the engine is going at 2,800RPM, even when off? Any idea which sensor could be the culprit here?
Sunday, November 21, 2010 - 05:25 pm, by: Justin Cook(Justin)
Hi,
I would say that the ECU might be playing some silly buggers with the fuel because it thinks you aren't moving. There are a couple of options.
1) Simplest, get an electronic sensor and hook it up to your ECU and buy a Apexi RSM or some other digital speedo and place it above your steering wheel.
2) Find someone who can hook you up an external electronic sensor. This is pretty difficult though.
Also get your capacitors replaced on the ECU and buy a new O2 sensor, might help with the fuel.
J.
Frank Csapo Tinkerer NSW Volvo 244GLE with 1JZ-GTE
Sunday, November 21, 2010 - 05:46 pm, by: Frank Csapo(264ttr)
Hi Justin,
If I can absolutely help it, I'd like to avoid going to an electronic speedo. I know this is probably the only solution to the issue, but I'm also thinking the money spent on an RSM and other gear might be better put towards an aftermarket ECU replacement.
The fuel consumption issues have gradually worsened over the last few months. When I initially did the conversion, my fuel consumption was over 300km/tank, which is my acceptable level. I've already replaced the O2 sensor, but it didn't make much difference. I have looked into getting the ECU capacitors replaced, but my soldering skills aren't good enough to solder caps onto a PCB, I will need to try to find someone local who can do it for me.
I suppose common sense would say to start simple, so I might try to get those caps replaced before moving onto more costly avenues.
Monday, November 22, 2010 - 01:13 pm, by: Aiden Cheese(Chillpen)
We get about 9-10L per 100kms in a 1jz converted nissan 260z
So.. if anything you should have significantly better fuel consumption than you currently have. Our ecu doesn't know the speed of the car (nor does the dash).
In the future we're looking at a electronic sender unit which sends the pulses as if it was a mechanical. These are the simplest ways to fix these things for us to do at home.
We've gone through maybe 5 full 45L tanks, and getting 400-500kms with reasonable fun driving.
How heavy is your car?
Frank Csapo Tinkerer NSW Volvo 244GLE with 1JZ-GTE
Monday, November 22, 2010 - 01:36 pm, by: Frank Csapo(264ttr)
So it sounds like the issues may not be from the lack of a speed sensor then...
Ideally I would like to get around the 400km+ mark in fuel consumption too. My car weighs 1360kg, I had it weighed as part of getting my engineer's certificate.
Monday, November 22, 2010 - 06:43 pm, by: Aiden Cheese(Chillpen)
When you put your foot down quick does it stall? Then again.. we disabled the TPS too. We had trouble and instead of um finding out what was wrong we unplugged the cable? IIRC I can look again at what we did.. but even with that unplugged it actually was incredibly responsive to the foot touch.. i hear that it may only respond after a 40% (or other largish) increase anyway in a short amount of time.
Map sensor of course is fairly important. We found that we had to clean the lines to the map sensor cause it got a bit gunky the first time we ran it..
Doesn't feel lumpy or anything does it? Im assuming if your fuel is bad, then you're missing power too. The 260 isnt much lighter than your car and its got a whopping lot of power for its weight. I think you should feel similar to that.
Frank Csapo Tinkerer NSW Volvo 244GLE with 1JZ-GTE
Monday, November 22, 2010 - 09:52 pm, by: Frank Csapo(264ttr)
No power issues at all really, runs smooth, accelerates nicely, boost comes on when it's supposed to. No issues with planting the foot down, it responds really quickly and feels fine. Hard to tell if there's a power loss, and if there is, it's only minor.
MAP sensor seems to be working OK, I unplugged it whilst idling and it coughed and spluttered and spat black crap out the exhaust, but as soon as I plugged it back in, it idled just fine.
No lumpiness at all, I can break traction in 1st, 2nd and sometimes 3rd, even with my locked diff.
Wednesday, November 24, 2010 - 03:01 pm, by: Frank Csapo(264ttr)
Definitely no leaks, I've had the car sitting there with the fuel pump running (engine off) and there are no mysterious puddles of fuel under the car, or any fuel smell as if it were leaking.
I've bought some capacitors so I'm gonna look into replacing the ECU capacitors to begin with.
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