Consult Data

[R33shaun]

Pretty much as the topic states, im having a few dramas with my R33 GTST s2.

Atm it coughs and splutters and has zero power for a while when its cold, itll hunt and just plain piss me off and play games but once it warms up its generally fine.

In the last few days its been getting worse and worse and is now starting to not come good and do the same when warm.

Looking at the consult data everything is fine and working normal except the A/F alpha reading sits on 100% all the time and the A/F alpha self learn is at about 97%. also the exhaust gas temp sensor is 5V all the time. Im not sure what the normal ranges are so any help would be greatly appreciated.

Car has a stock ECU (speed limiter removed) stock turbo, FMIC, stock BOV, running stock boost atm because if i raise it even a little it coughs really badly.

Also has RB30 botton end with a RB25 head, coils are brand new splitfires, new Airflow meter, cleaned IAC and throttle body. Im also just about to get new plugs and see if that helps.

If someone could post up a consult log or give me some ideas of normal readings that would be great, also any other ideas would be more than welcome.

Ill post up a consult log when i get a chance.

Cheers shaun

[R33shaun]

It also has a new O2 sensor (replaced 500km ago) and got new plugs and a heap of vacuum line today so i can replace all the vacuum lines tommorrow.

Drove it this arvo and had no problems at all, started fine warmed up for about 5 min while i was getting the Consult software to connect then drove no worries.

The temp is also sitting at 102 degrees? but it was a hot one today (around 35 deg). It has an magna thermo bolted to the radiator which runs off the ignition rather than the crappy viscous crank driven one.

I really hate intermittant faults, any one have any ideas?

[Moodles2]

A stock 2.5l ECU powering a 3.0l engine?

[R33shaun]

yeah for the moment, getting a new ECU when the shops open back up in a few weeks. I was going to get a link but now im thinking Power FC D Jetro. I think the stock AFM is maxing out when i wind the boost up which is why it coughs on 10psi but that doesn't explain the stuttering and coughing when its cold. It was running fine for 2+ years with the stock ECU its only been the last few months i've had problems. Im really just after a Consult Data log to compare to my readings so i can see if there is any obvious fault.

cheers shaun

[mad082]

ok a few things,

1: what temp sensor is being used? the rb25 one?

2: how has the speed limiter been removed? has the speed wire been cut or is it a remapped ecu?

if the car is running at 102 degrees then it is way too hot. either the thermostat is shagged, or the water pump, or the radiator..... or a combination of the 3. the stock vicous clutch fan are actually a very good system when (when in good working order) and are not worth replacing unless the clutch has stuffed up.

running the 3.0L engine off the 25 mapping is more than likely causing issues. are you still running the stock 25 injectors? if not then that will be part of the problem.

A/F reading will have very little to do with the problem because you can run the car perfectly fine without an o2 sensor. however the EGT reading interests me since the rb25's never had an EGT sensor as far as i am aware.

[R33shaun]

Its using the 25 temp sensor and I replaced the fan because it was shagged, im fairly sure that the ecu was remapped at some stage but i have no idea what was done.

Ill replace the thermistat tommorrow and flush it all out again and see if that drops the temp at all, the radiator was only replaced a couple of years ago so it should be fine but ill clean it out and check it over anyway and the radiator cap is also new.

According to the manual the R33's have a cat temp sensor/exhaust temp sensor to bring up a warning when the cat dies. Not sure what its meant to sit at though or if its just an on/off kind of thing.

Its running the stock 25 injectors, which are on my list to replace when i do the ECU as they were nearly maxed out when it was tuned with my old e-manage for 10PSI.

Also just to annoy me some more its been all good for the last two days so i cant get a log of when its running crap.

[NewKleer]

EGT always reads 4.98v on nearly all cars ive seen, im not even sure they did this EGT sensor right in the consult unit (i.e. it might not even be a voltage reading by a mis-interpreted switch status, e.g. EGT is 'not hot' or 'too hot'). the 100% and 97% isnt anything to worry about.

[R33shaun]

EGT always reads 4.98v on nearly all cars ive seen, im not even sure they did this EGT sensor right in the consult unit (i.e. it might not even be a voltage reading by a mis-interpreted switch status, e.g. EGT is 'not hot' or 'too hot'). the 100% and 97% isnt anything to worry about.

cheers, thats one less thing to look at.

It started coughing and playing up again tonight but the air temp here atm is a lot cooler than it was today so im thinking maybe a dry joint in my AFM. Ill pull that off and check it tomorrow as well.

[R33shaun]

Any one know how to upload consult data? i cant seem to get it to work.

I think i know why its coughing so much when its cold. It seems that the airflow meter maxes out (5V) on WOT when its not completely warmed up or if the outside air temp is a bit cooler.

When its warm it peaks at around 4.7V. Im guessing when the AFM maxes out the ECU cuts ignition or goes into limp mode, which would also explain why it does it when i raise the boost using my Greddy Profec as it spools up alot quicker (even only a small increase in boost causes it to cough badly).

I might try lowering the gain on the boost controller so it comes on a bit slower and set it for 9PSI and see if it makes any difference.

Looks as though ultimately im going to have to wait until i change the ECU before i can wind up the boost ( I only want to set it to 12PSI)

Cheers shaun

[NewKleer]

turn on the 'log' checkbox in ecutalk then view the gauges etc as normal and it will log a file to same place as the ecutalk exe. then zip that and upload it as an attachment in your post.

[R33shaun]

car bad start.zip

Thats a log from when its cold and running sh*tty, hopefully it worked, it should open with the OBD scan tech software. I have version 1.29 if that makes any difference.

Anything stand out to anyone cos im stumped..

Cheers shaun

[NewKleer]

should have used ecutalk for the logs, scantech logs dont include time and hard to graph the on/off sensors

and need to be able to tell us when in the log its 'coughing' e.g. here you have 3 goes at the accelerator (it stays >750rpm all the time) and then a pause, and in this time the rpm drops around 600s, and then another couple of bigger stabs (the second goes pretty high on the MAF for no load...its a RB25DET maf right?). so is this coughing in between those stabs where its doing it for a while?

anyway, if you graph it, notice how your AAC is close to 100 - this means it has no room to let more air in to keep idle higher. so your idle screw might be set too low, or you might have dirty AAC. try the base idle mode, its in free conzult if not in scantech, make sure engine warmed up fully, and see how the engine idles once u start the base idle/timing mode - if at a low RPM (or immediately stalls) then idle screw likely set too low.

[R33shaun]

Thanks man ill have a go at that tommorrow arvo, Ill also try to get a better log of it using ecutalk when its playing up. I still havent had a chance to do the plugs or vacuum lines yet either (been raining up this way a bit). Ill clear the junk out the garage tommorrow and stop procrastinating.

Its running the stock R33 AFM (pink label). It mostly hunts on idle and chugs black smoke for a few minutes but once it warms up a bit it settles down. It also intermittant some days i have no dramas at all.

The coughing happens randomly when im driving along and give it a bit of stick. It'll either cough at around 4 grand (cough as in die completely for a half second), sputter and feel really sluggish or pull through to 7 grand (still has a bit of a flat spot between 4-5grand but pulls through it).

Coils are brand new, plugs <3000Km old as well but im changing them again anyway

Cheers for the help

[R33shaun]

Righto, think ive managed to fix it, I changed my plugs today with bcrp6's gapped to 7.5mm, cleaned out my AFM (wasnt dirty but blasted it with contact cleaner anyway). Also replaced all my vacuum lines and replaced the rubber joiner between the throttle body and intake pipe (was a bit worn but no split or cracked).

I let it cool right down then took it for a drive, i think ive somehow deleted the consult software from my laptop and cant seem to find the disk so i used scantech again.

First one is straight up after i let it idle for about 5 min, running wastegate boost (gets up to 10PSI???)

car cold.zip

Second run after it was warm i set it to low boost on my controller ( starts at 8PSI and builds to 10.3PSI at about 3500rpm and holds till 7000)

boost.zip

Third one is when i set it to High boost (11.7PSI comes on hard). It maxed out the AFM and coughed so i set it back to low boost. You can see the AFM hit 5V just before the revs drop off about 150 frames in when it gets to 5000RPM.

boosthigh.zip

It was running fine on low boost after that for about 40min driving fairly hard then the turbo started to surge in second gear at about 3/4 throttle and make a fairly loud whine/turbo spool hiss and also a bit in 3rd but not as bad. No idea what caused it to do that but.

It also felt a bit sluggish considering it was on 10PSI, not sure if its overfuelling or not running enough timing?

Changing the plugs also seems to have fixed my temp issue, even after hiding it for a while it still only got to around 85 deg. Also the IAC seems to have settled down.

Cheers for the help and any ideas on the surging/ sluggishness would be great.

Thanks, shaun

[koduRB25det]

ok a few things,

1: what temp sensor is being used? the rb25 one?

2: how has the speed limiter been removed? has the speed wire been cut or is it a remapped ecu?

if the car is running at 102 degrees then it is way too hot. either the thermostat is shagged, or the water pump, or the radiator..... or a combination of the 3. the stock vicous clutch fan are actually a very good system when (when in good working order) and are not worth replacing unless the clutch has stuffed up.

running the 3.0L engine off the 25 mapping is more than likely causing issues. are you still running the stock 25 injectors? if not then that will be part of the problem.

A/F reading will have very little to do with the problem because you can run the car perfectly fine without an o2 sensor. however the EGT reading interests me since the rb25's never had an EGT sensor as far as i am aware.

mate,

I also having similar prob. just asking, how this related to cut speed limiter wire from ecu. coz i have notice one wire cut from my ecu [series 2]. not sure about the wire. thanks

[NewKleer]

looks like its time for the bigger AFM, and proper tune with nistune (or normal remap, whatever). isnt it normally recommended u go Z32 AFM? (from memory thats what brother did with his - something bigger than RB25 AFM anyway). cause its going to be hard to work out any issues due to not having a proper tune and AFM for the bigger capacity, from any legitimate problems unrelated to that.

[Sarumatix]

Brave person what puts a twin cam 3L RB in and runs a factory tune.

[R33shaun]

Had a breakthrough today while checking my car again (coughing was getting way worse).

Pulled the AFM off for about the millionth time and decided to gut it to check the solder joints, a couple of the pins are dry jointed!

So ill touch these up when my housemate gets home with the soldering iron and see if this fixes it.

Moral of the story dont assume new parts are any good!

Its also going in next week for a vipec and tune so this is just a tempory fix to get me to work next week.

Cheers for everyones help and ill post back later with the outcome

shaun

[bubba]

Brave person what puts a twin cam 3L RB in and runs a factory tune.

Works fine, I drove mine around for a few months untuned, it just maxes the afm rather quickly so you don't give it heaps of shit or rev it out. The load of the engine is calculated from the airflow, more flow, more load, different cells.

[R33shaun]

Had a breakthrough today while checking my car again (coughing was getting way worse).

Pulled the AFM off for about the millionth time and decided to gut it to check the solder joints, a couple of the pins are dry jointed!

So ill touch these up when my housemate gets home with the soldering iron and see if this fixes it.

Moral of the story dont assume new parts are any good!

Its also going in next week for a vipec and tune so this is just a tempory fix to get me to work next week.

Cheers for everyones help and ill post back later with the outcome

shaun

Problem fixed no coughs or splutters at all!