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Low idle when warm - MAF and TB cleaned - TPS broken?

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wenguin
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby wenguin » Sun May 24, 2015 1:18 pm

Soiled wrote:That's an AS200 cluster. Redline, and fuel economy meter give it away. Which would explain the difference in the ECU and the cluster rpms.

Thanks for that mate. The fuel economy meter seems to work, weirdly.

My immediate thought was mileage, but the mileage has been recorded since it came to Europe in 2007 and seems fine so it must have happened in Japan. Car condition suggests the mileage is fairly accurate at least, so haven't been ultrascammed 8)

This is especially odd now, as the OBD2 reading is probably accurate - 750rpm warm idle - is this about right?

As a general update, currently stripping down engine to do timing belt / water pump and possibly rocker cover and spark gaskets.

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RS Tom-Hundred
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Tue May 26, 2015 11:38 am

Aha! That solves that one then :P

I still havent got around to sorting my Torque app out but when I do I'll let you know accurate idle figures :)

BTW, I read somewhere of someone who put a new rocker gasket and still had leak issues. When I did all the engine work on mine, I decided to use gasket sealer in the recess of the rocker cover and also put a smear on the face of the original gasket too. So far no leaks and that was a month or two ago :)

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby wenguin » Thu Jun 18, 2015 10:43 am

Did timing belt, aux belts, plugs, coil and new coolant. Got the car on the road yesterday, driven about 15 miles and running like a bag of dicks.

Idle is 600/700 but really lumpy, exhaust sounds terrible, whole car sounds like a mix between a tractor and a dirty diesel.

MAF and new coil on order to try those, things after that to check: o2 sensors, vvti solenoid, voodoo curse.

Also, does anyone know what the little plastic cap on the left near the intake is? It's like a little hat, white/yellow in colour:

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RS Tom-Hundred
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Thu Jun 18, 2015 11:41 am

That's the fuel pressure regulator/valve on the fuel rail matey :)

Shame about the rough running - hope you get it sorted :) Did you get my PM about link to the OBD2 adapter you used? keen to get mine working and compare your TPS numbers to mine.

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby wenguin » Thu Jun 18, 2015 3:11 pm

RS Tom-Hundred wrote:That's the fuel pressure regulator/valve on the fuel rail matey :)

Shame about the rough running - hope you get it sorted :) Did you get my PM about link to the OBD2 adapter you used? keen to get mine working and compare your TPS numbers to mine.

Apologies, i did yea I'll get the link to the one I used.

I have two I got off amazon, both relatively cheap (one £5 one £15). the £5 one works in the altezza but not in my dad's ford cougar - it drops out a lot on the altezza e.g. after error code runs.

the £15 works in altezza and the cougar, still drops out - i exit the app and open it again. torque seems to s@3! itself when it loses connection - it starts cycling through all the connection types instead of just using what it does on first boot and using the JDM ECU initialisation code

will screwing that screw in affect the running?

i've error codes for MAF, O2 sensor and one other thing - going to see if I can clear the MAF one with the replacement and see what happens from there. not sure why it runs worse now we've done the belt - could the timing be off now? belt didn't break, changed it doing maintenance

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Tosh21
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby Tosh21 » Thu Jun 18, 2015 11:46 pm

That thing is a pulsation damper, to try keep the pressure even across all the injectors IIRC. Weird that it's running bad all of a sudden, mine is like that sometimes it's such a picky car it's ridiculous. I did an oil change and then my fuel pump cut out after 10 miles :roll:

Is it a misfire?

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RS Tom-Hundred
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Fri Jun 19, 2015 10:10 am

Cheers mate :) Does the fiver one cut out when using it for just displaying dials or only when you do error codes etc. Might chance that one and then send back to Amazon if too glitchy and get the £15 one :)

YEah, the valve thing is like Tosh says, I probably confused things a bit by saying it is a regulator as such (cos I dont think it changes the pressure like an adjustable fuel pressure regulator) but it will regulate the pressure across the rail to give smooth supply of fuel to all the injectors. That's how I understand it anyway - is that 100% Tosh?

I read on the NZ club that if you lift the cap there is a screw under there (that I dont think you should tighten or loosen unless you know more about how it affects things!!). The screw section should sit lower when the car has been sat for a few hours (and fuel pressure has dissipated) and then this should pop up and stay up when the engine is cranked over and started (eg. when fuel pressure is there).

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby Cam2Tezza » Sat Jun 20, 2015 9:15 am

Since I've been fiddling with TB issues and TPS lately I guess I'll join in over here lol, though I don't have much to say. Since I swapped my TB for another one, with accessories off, my car idles as low as 650rpm(down from 800 with the old TB) and it vibrates a little, also I can't hear my engine/exhaust with the windows down. All I've done with the TPS is buy a new one, then set it to 0.78v measured at the ECU and it runs pretty well now, but I have a subtle jerk when I tap the gas pedal in 1st and 2nd, so I may fiddle with the TPS a little more. It's like boost for a fraction of a second but I can live with it for now. Regarding TPS position each one seems different, cuz the one that was on my "new" used TB would read 0.71v, while the new TPS i bought read 0.46v in the same position and I had to set it close to the middle to bring it up to 0.78v, and peaks at 4.37v opening the butterfly by hand with throttle motor disconnected. My old faulty TPS read 0.86v at the lowest setting, opening the butterfly slightly would then cause voltage to drop before going back up. By the way I've read that our cars are supposed to sound like diesels at idle :lol:

PS your engine bay looks really clean, any tips to share?

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby wenguin » Wed Jul 01, 2015 5:44 pm

That was a photo I stole from somewhere.

My guess is it's a low Japanese car in japan, or a low mileage car not long out of Japan. Or someone with OCD haha

BTW I cured the idle/shaking problem with new coils (2 of them). Still have a slight shake when stopping at lights but nothing that changes on the tach. Will order 2 new coils next month and have a full set installed.

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RS Tom-Hundred
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Thu Jul 02, 2015 10:58 am

Good luck and interesting to see if the coils completely solve it :)

With regards to the engine bay cleaning, I did mine all while I had the engine out so obviously a lot easier but I just used a cheap engine degreaser in a spray, a toothbrush and a paint brush and then used old rags to wipe it all off. Takes a long time but be patient and it looks good when done. Decided to use the rags to wipe off rather than water as less risky and easier in the long run anyway! Can also use wire wool to bring up aluminium bits like AC pipes, intake manifold etc

Here's a photo of mine after the clean and paint up (hope Damien doesn't mind be quickly spamming his thread)
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Tosh21
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby Tosh21 » Sat Jul 04, 2015 8:26 am

Wow that looks awesome! Wish I had the patience for that

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby Cam2Tezza » Sun Jul 05, 2015 2:18 pm

After I fixed my TB problem I'm now onto the fuel pump and regulator cuz it's only giving me ~35psi and drops to 0 immediately after I shut it off(causing me grief on warm restart). Pulling the EFI relay also causes it to die instantly. I took out the pump and disassembled it, and found part of the regulator O ring was pushed out , I'm unsure whether a regulator stuck closed would cause this. But anyway I'm replacing the whole pump assembly for peace of mind. I wonder if it's the cause of my jerk when i first apply light throttle as well..

As for aesthetics I want to paint my car white, but going the rustoleum roll on route cuz of budget restraints. Also found a set of IS300 leather seats but sadly the rears were gone when I finally had time to check them out at the salvage yard. :( Maybe a diy project for the future...

Edit: I've now reassembled the pump and tried it, warm restart seems to be much better. But the point where the engine catches still sounds weak. However power in first gear and across the rev range is back!

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RS Tom-Hundred
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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Mon Jul 06, 2015 11:55 am

Glad it has improved a bit and hope the pump helps too :)

Tosh21 wrote:Wow that looks awesome! Wish I had the patience for that

Cheers mate. To be honest, I wasnt going anywhere in a hurry at the time with the engine out and the crank being reground so it made sense to clean and paint everything up prior to refitting it :)

Ironic things is that the whole block is bright red but you can hardly see any of it once it was all back in the car and the intake, exhaust and ancillaries are back on! LOL

Damien - have you got all the coil packs changed now and how is it running??

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby RS Tom-Hundred » Wed Jul 08, 2015 12:21 pm

Massive thanks to Damien (wenguin) as I have now got the OBD2 adapter he suggested and it works fine with the coding pasted into Torque :)

Here are some screenshots to show the TPS values that Torque gave me in different situations last night and this morning:

6.30pm (Engine off, approx 1 Hour Cool Down [since getting home from work], No Throttle pedal)
Image

6.30pm (Engine off, approx 1 Hour Cool Down [since getting home from work], Full Throttle pedal)
Image

7.45pm (Engine off, approx 2.5 Hour Cool Down [since getting home from work], No Throttle pedal)
Image

7.45pm (Engine Idling, Engine Warm, No Throttle pedal)
Image

10.00pm (Engine off, approx 2 Hour Cool Down [since getting it warm at 7.45pm ish], No Throttle pedal)
Image

10.00pm (Engine off, approx 2 Hour Cool Down [since getting it warm at 7.45pm ish], Full Throttle pedal)
Image

08.00am (Engine off, Overnight Cool Down, No Throttle pedal)
Image

NB. I changed the maximum on the Timing advance gauge from 30 to 60 after some reading so only look at the numbers rather than the needle position)

Hope that helps?

Comparing those figures roughly tothe situations you tried yours in (quoted you and put my figures in red)

wenguin wrote:
OBD2 TPS % @ engine off, throttle closed = 15.3% 14.9%
OBD2 TPS % @ engine off, throttle fully open = 82.4% 81.6%

OBD2 TPS % @ engine on, warmed up, throttle closed = 13.3% (revs @ 761) 12.5% (revs at 702) but got 13.3% when engine off but still hot

OBD2 'timing advance' @ engine on, warmed up = 19.0 14.0


Based on that then I wouldnt say that yours is far different to mine. And just to add, the yellow paint (from factory?) is still on my adjuster screws.

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Re: Low idle when warm - MAF and TB cleaned - TPS broken?

Postby wenguin » Thu Jul 16, 2015 11:06 pm

Thanks for that, Tom. I'm fairly confident all is well in that department.

Idle still wasn't perfect with the 2 new coils, so I've 2 new ones I should get tomorrow or Saturday and that'll be that sorted.

Still hunting for an exhaust, but having little luck.


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