EDS OBD2 - trying to diagnose bad idle issue

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Agoold90

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G'day everyone,

My 2010 yd25, 160,000km seems to be experiencing a fault that I've read alot about of on this forum - bad idle and drop in revs, particularly when cold.

I've just started troubleshooting and trying to use my EDS OBD2 (4WD Supacentre one) and trying to read fuel rail pressure (FRP) and manifold absolute pressure (MAP). FRP doesn't seem to be an option and MAP just reads 0.0 and never changes.
Just wondering if anyone has this same data scan unit and get the same result, i.e. no FRP and 0.0 MAP?

Cheers
Alex
 
I'd use a Bluetooth OBDII ELM327 device and an app like Android's Torque. Cheap, simple, effective.

However, before investing in any other tools, it really is worth grabbing a can of Liqui Moly Fuel System Treatment and throwing the contents in the fuel tank. See how it's going after 100-200km. If it's improved, you had a dirty SCV (common issue) - you might need to replace it at some point. The SCV is the usual suspect for poor idle.

The MAFS (lives the air pipe just out from the air filter box) can get dirty too, don't use anything other than electrical contact or MAF cleaner on it. Never insert anything in the small hole that should sit in the middle of the airstream.

Finally, don't worry about the turbo. At idle, it's not needed. The intercooler might be full of oil (definitely possible) so you might try cleaning that, but the turbo won't affect idle performance.
 
No
I use a Vgate obd2 scanner and the torque app like Old Tony. I can read FRP MAP plus more.i did try a cheaper unit first it was rubbish could not read jack. I don't trust electronics from supercentre apart from lights etc. Take it back, buy a better one.
 
Thanks all. The unit was given to me so no real loss there. I also read the reviews KevinE...certainly does note rate well :).

Since my first post, the car stalled at idle and I managed to get a P0089 error - fuel pressure regulation failure; pointing to SCV.
I have changed the SCV and run Liqui Molly cleaner (I really rate that stuff Old.Tony, I've used it for a few years now!) which has resolved the bad idle issue. Thanks.

However, as I was closing the bonnet, I thought I'd quickly check my coolant and noticed engine oil in the coolant. Also in the reservoir.
Looking at some threads on here, I will check the oil cooler as my first port of call.
Intercooler also weeping oil at the hose clamps. I'm not sure if related as not sure where an air/water/oil exchange could occur. I'll remove the intercooler and clean out at some stage as you suggested old.Tony.

Will update when / if I diagnose oil in coolant.

Cheers
 
Oil weeping from intercooler hose joins is a boost leak issue. There's oil vapour ccoming out the PCV which enters the air intake just in front of the turbocharger and it then gets pumped through under pressure into the intake manifold. It will exit any boost leak making the leak obvious. This will NOT contaminate any other system.

Oil in the coolant can come from two possible sources: a leak in the engine (unlikely it's the turbo, but that's also possible) or the auto transmission cooler which is inside the radiator. Check your trans fluid to see if it's milky.
 

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