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Hey. Just ironing out my engine problems. I got a dyno tune and the car runs mint. I didn't have time to leave it at the shop for cold start tuning and its unavailable where i live. So I might give it a go.

It's also got a slight miss on idle and at low revs. It's real hard to hear but it's sometimes there.

Ive got power fc, hand controller, datalogit and wide band.

The issue I'm having is the car wouldn't start first pop when it's dead cold. My engine temp never gets colder than 30 cause of my location. It sometimes took 3 goes.

So I had a read up and first things first I took the atmo bov off and smashed it with a hammer! I've blocked the vacume line. The car starts first time now.

The issue I have is for the first minit of warming up it has a real flat spot after that it's fineThe engine doesn't want to rev. Not that I want to bash the limiter or anything.

Let's just say my girlfriend wanted to shift my car first thing in the morning, turns the key, lets the clutch go, gives it some gas and it will stall or coughf.

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Ok for thoes listening, I've got the fueling sorted. Just adjusted the water correction tables. Was way too rich. Got em 13.5 at 30^deg. It's punchier.

I've got this stupid miss fire I can't get rid of.

Here's the symptoms.

Idle sounds lumpy/smooth

And when I hold it at 1500 2000 2500 3000 it sounds like a fully sick lumpy cam gtr! (Not the sound I want)

Seems to rev ok. Las time I drove it had the miss but boosted 18psi sideways at the track just fine all day!

I chucked a new set of plugs in, changed the gap from .8 to 9.3 didn't make a difference.

Changed afm to a spare one. Made no difference.

Removed bov still nothing. Starts better tho.

I've got a feeling it's the cas but don't want to throw 500 bux at it. I'm over it.

What else can I check?

02 is newish

Got spitfires there newish

Band new injectors/pump

Ok for thoes listening, I've got the fueling sorted. Just adjusted the water correction tables. Was way too rich. Got em 13.5 at 30^deg. It's punchier.

I've got this stupid miss fire I can't get rid of.

Here's the symptoms.

Idle sounds lumpy/smooth

And when I hold it at 1500 2000 2500 3000 it sounds like a fully sick lumpy cam gtr! (Not the sound I want)

Seems to rev ok. Las time I drove it had the miss but boosted 18psi sideways at the track just fine all day!

I chucked a new set of plugs in, changed the gap from .8 to 9.3 didn't make a difference.

Changed afm to a spare one. Made no difference.

Removed bov still nothing. Starts better tho.

I've got a feeling it's the cas but don't want to throw 500 bux at it. I'm over it.

What else can I check?

02 is newish

Got spitfires there newish

Band new injectors/pump

Have you checked the timing. Most times it can be only 3 things air fuel and spark. Unless it has an engine component failing but it would be more constant if it was mechanical

Has the CAS been removed after the tune?

Has anything been added/changed after the tune?

If you have played around with the AAC Valve after the tune was done then it can affect the idle - the tuner would have set this all up on the initial first tune

If your timing is out then also the fuel mixture wont be igniting at correct position - maybe just put a timing light to check the timing

Also if your tuner has performed 90 percent of the initial tuning and doesn't necessarily need the vehicle back - if he has hit every cell in your mapping and has also done the final power run - depending on how extensive the tune was they usually start with idle 1500 2300 3000 5000 then power runs and varies from tuner to tuner - if all this has been complete then your tuner if you explain to them what is happening then he/she should be able to email the tune file to correct the cold start issue. As long as you have the software and cable to upload to your FC

I would be cautious on changing anything after your tune because your tuner should have checked everything - if you could log a file from your FC either in FC edit or Co-pilot or whatever software you use then you could send that to your tuner and he would advise immediately whats wrong. Could be as simple as AAC or TPS or MAF maybe CAS moved slightly or something has moved or come loose which will affect overall performance and AFR's

If your tuner wont do this then find another one.

All the best and hope you get the issue sorted.

Edited by tuning_vs_hardware

I'll be sure to set the base timing again I'll do that next. yes I had the cas out because I heard knocking from the cam cover. one of the bearings has collapsed, I some oil in it and put it back in and the knock has gone.

Here's the thing about the tune.

In had the car on the trailer, drove 2200kms broome to Perth. Dropped it at the tuners, picked it up. Drove to the race track the next day unloaded it. Done a drift session.

A passenger in the car said to me "this thing has a miss fire". I ignored it and continued to drift as it performed well.

The next day I drove 2200kms home. (Yes 2200kms). I have never driven the car since.

That piss want tuner should have picked up the miss. Does anyone want the shops name?

I'll be sure to set the base timing again I'll do that next. yes I had the cas out because I heard knocking from the cam cover. one of the bearings has collapsed, I some oil in it and put it back in and the knock has gone.

Here's the thing about the tune.

In had the car on the trailer, drove 2200kms broome to Perth. Dropped it at the tuners, picked it up. Drove to the race track the next day unloaded it. Done a drift session.

A passenger in the car said to me "this thing has a miss fire". I ignored it and continued to drift as it performed well.

The next day I drove 2200kms home. (Yes 2200kms). I have never driven the car since.

That piss want tuner should have picked up the miss. Does anyone want the shops name?

Sounds like something was missed on the initial tune - I know some tuners get a bit funny about customers hanging around while they are tuning the vehicle - but all in all its the customers car and paying good money to do the work - I was lucky to ask many questions and pick the right tuner for my current R33 - goes back in the week of January 11th

I feel for you though being 2200km away thats insane - you would want to hope the tuner can easily send a file to you or help with your issue.

I would check the CAS - some people when they remove these mark them with a paint pen or permanent marker and sometimes they appear to be back at original pos but out slightly - I would advise 3 hairline marks with a scribe this ensures pinpoint accuracy when put back in, or just chuck the light on hoping the tuner hasnt set it to a different position than what the light reads.

As for the guys name in Perth I wouldn't publicly display it unless they dont help with the after hours or customer service

Do you have access to your Power FC via FC Edit? If you have FC Hako or FC Data Logit if you could PM your tune files - INJ MAP IGN MAP SETTING 1 through to SETTINGS 5 then I could take a look. Either screen shot the pages or send the .dat file

Edited by tuning_vs_hardware

I just set it to 15 just then. Yeh it was out was on about 18. it seems to get better when it's running at 80degreese. I can only hear it defiantly when I hold it at 3000 in neutral. There's somthing defiantly there or there abouts. So frustrating.

Do you have your tuners contact number for after hours always make sure you have mobile contact so you can text them or what ever - ask him what he set it on when he tuned the car. Remember this base setting will coincide with your ignition map right through the rev range. So if it was 14 below and your tuner has that mapping at 14 and you have it at 15 then the mapping will be out by 1deg which in turn would affect AFR as the fuel mixture has been tuned with the ignition map and fuel map - TPS and MAF

Also did the tuner change the position of the TPS and mark it when he had it set to the correct position - some tuners will just move them into place an extensive tuner will tick all boxes. You could see if it has moved or wasnt done up tight - or check the Closed Throttle and WOT voltage - even just turning the screws on the TPS can cause it to move

As for your plugs I wouldn't go more than 0.8mm

To save yourself from pulling your hair out and getting frustrated with the car :) - I would definitely contact this guy and query him on the issue like XGTRX said - ask him what he had it set on - contact this guy and bug the hell out of him until he fixes the issue. Call him and post what he recommends

We could sit here typing all the problems we think it could be but it could be as simple as moving something or tightening a pipe because its loose while you still getting boost but extra air after the AFM - remember the vehicle only calculates air that has gone through the MAF to calculate fuel - a misfire can even be from too lean fuel mixture right down to timing or spark ignition and so on.

Do you know its more frustrating sitting here 1000's of Km's away and not being able to help fix the vehicle as much as we would like - Grrr - I hate helping diagnose via PC message I am more hands on type hah

I wish I was closer to Broome I would be more than happy to drive over and perform some testing with you - take some parts off my R33 to put on yours to see if its sensor issue.

Edited by tuning_vs_hardware

Just wanted to post this - have you tested the cold start valve for operation? I am pretty sure its function opposite to a thermostat so it works with cold temperature the colder it is the wider it opens.

post-141798-0-30172200-1451547749_thumb.png

Test its function and also clean it out - double check no splits in the hoses that run from each side of it as well.

Some people warm them up then put them in a freezer or fridge for function - like boiling a thermostat

Yeh I'll give it a go tommoro although it's tight under there. I cleaned it 2 years ago only done 500kms should be clean. Dunno about function tho. Gonna clean the spitfires and put dialectiric grease around the boots and clips. Got rid of the knocking in the front as it came bak. Cambelt was too loose. Gonna put a resister and eliminate the knock sensors aswell. my wiring might have been poor when I put the freddy manifold 2 years ago although it seems to read ok. Gonna check fault codes and also tps volts

Yeh I'll give it a go tommoro although it's tight under there. I cleaned it 2 years ago only done 500kms should be clean. Dunno about function tho. Gonna clean the spitfires and put dialectiric grease around the boots and clips. Got rid of the knocking in the front as it came bak. Cambelt was too loose. Gonna put a resister and eliminate the knock sensors aswell. my wiring might have been poor when I put the freddy manifold 2 years ago although it seems to read ok. Gonna check fault codes and also tps volts

Yeah its the worst place to work on under the manifold and ya have to love those factory hose clamps sometimes.

Excellent hope it goes well and we can see some posts when you get the problem sorted.

Enjoy your new year.

Stupid knocking is back.. It's noisy on idle. And up to 2000 revs. Comming from the right hand cam on cylinder 1. It's not the cambelt. What noise does lifters make? I thought they were more tap tap tap. Mines knock knock knock.

Anyways cleaned coils and used dialectic grease to try sort my miss. Dunno if it done anything. Looked like number 4 was a little unburnt so hoping I've cleaned that up.

Tps volts were good.

When I hold it at 3000 rpm now it fluctuates from 2800-3100 wtf is that? Somthing air related I bet.

I just set it to 15 just then. Yeh it was out was on about 18. it seems to get better when it's running at 80degreese. I can only hear it defiantly when I hold it at 3000 in neutral. There's somthing defiantly there or there abouts. So frustrating.

I wouldn't be touching the cas if it has been tuned set at say 18.. now you've just lost some power as your entire map has 3 degrees less timing.

still safer than those guys advancing their cas to 15 when it was much lower.

Also that fluctuation at 3k rpm could be from a lean spot on the tune that was never tuned on the dyno as the tuner didn't hit that load point or didn't tune cells around certain load points.

  • Like 1

Yeh well I'm doubting the tuner touched the timing gun or cas as I had it set to spot on 15 b4. His tuning time was only an hour or so before he rang me back. So I'm assuming it would be the same. All I can do is ring him and ask but he won't remember it was months ago.

This is axactly where the sound is comming from.

What can I do with this apart from get a new shell?

I'd be to scared to see what's under the cam. I bet the oil supply is blocked with alloy aswell although there is signs of oil on the cam.

I'm not havn a good run I tell ya. I'd love to burn it.

post-133405-0-27169700-1451721443_thumb.jpeg

post-133405-0-73432600-1451721470_thumb.jpeg

I think its time to pull the cam out. If the other half of the cam tunnel looks like that then it will only cause problems. Pull the cam out now

You cant just go buy a new cam cap anyway. They are matched to the head so the cam caps off my engine wont work on yours. Best case scenario is that you will need to pull the head off to get the new cam cap tunnel bored to the head (if you want to do it properly)

  • Like 1
  • 6 months later...

Sorry to wright on your conversation, but i have a similar issue.

I have mycar tuned and and runs fine but my car doesnt start when cold. Takes time to start. I checked my pfc comander and the temperature sensor shows like minus 22 degrees (-22°c) wich is impossible. Try to replace for a new one and same problem again.

Do you guys have any ideas to sort this out please?

Thanks 

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