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Throttle body issue ?

wannaeatyourbrains

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Most usual cause is vacuum leaks. Brake booster, HVAC line at the back driver's side of the plenum, the purge line elbow on the front of the throttle body, bad plenum gasket, bad fittings for the PCV lines on the plenum, or that black Y-piece is cracked. That last kind of crack can be really hard to see. You gotta pull it out, block the end of the pipes and blow in it to know.

Spark plugs for sure. Next most common. You said you checked the coil packs, right?

Then you could look at the injectors. Remove and clean.

Sometimes just the throttle body is stuffed. Can you borrow one from someone to swap and see if it makes a difference?
 

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Most usual cause is vacuum leaks. Brake booster, HVAC line at the back driver's side of the plenum, the purge line elbow on the front of the throttle body, bad plenum gasket, bad fittings for the PCV lines on the plenum, or that black Y-piece is cracked. That last kind of crack can be really hard to see. You gotta pull it out, block the end of the pipes and blow in it to know.

Spark plugs for sure. Next most common. You said you checked the coil packs, right?

Then you could look at the injectors. Remove and clean.

Sometimes just the throttle body is stuffed. Can you borrow one from someone to swap and see if it makes a difference?


thank you for the reply its awesome to see a commy in Mecca

it really made the car idle smother cleaning the throttle body and replacing the back 2 coils but now since cleaning the pcv valve ita trouble the line did come off with no pulling etc it just gently lifted off is this normal?

ive got a spare throttle body from wreckers a set of spare genuine 2nd hand bosch coils only did the 2 i could get to

its started to play up just now as i thought id spray throttle body cleaner in to the pcv valve for the time bein until i remove valve cover late next week as I'm awaiting for a top plenum gasket dont want to risk it incase its the orginal oh and spark plugs
 

wannaeatyourbrains

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You mean the PCV valve pulls out more easy now once you pulled it out already? That's OK. It's a suction ventilation system not a blowing one, so it doesn't pop out.

If the line doesn't clip on top any more you broke the clip. It has a plastic tab you have to pull to one side to release it before you pull it off.. But it is OK to use hose to replace it if you broke the quick release. Or you could glue it on there with a bit of silicone gasket.

If you got oil in the intake the PCV system definitely isn't working properly, and needs to be drilled and cleaned out.

You can see if the coil packs are sparking well by pulling them out, lying the end of them on the block and turning the motor over when you got the plenum off. Do it in the shade so you can see.

Chances are your problems will be solved when you change the plugs.

Pull it all apart, and put it back together with new plugs, coil packs you know are sparking good, no vacuum leaks, a clean throttle body, and a clean and drilled out PCV system and chances are it will be good as new.

If that doesn't resolve it, you gotta try cleaning the injectors, and swapping your throttle body over.
 

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Also what is this PCV valve mod

as i have removed a pipe in the back of the passenger side valve cover which then goes to the intake piping tube and it looked drilled out or such the little 1/8" hole i believe.
Have a look in the “how to” forum.
 

Sliding_vt

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all good i under stand where and how to do this PCV valve mod just waiting for top manifold gaskets
 

Sliding_vt

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Most usual cause is vacuum leaks. Brake booster, HVAC line at the back driver's side of the plenum, the purge line elbow on the front of the throttle body, bad plenum gasket, bad fittings for the PCV lines on the plenum, or that black Y-piece is cracked. That last kind of crack can be really hard to see. You gotta pull it out, block the end of the pipes and blow in it to know.

Spark plugs for sure. Next most common. You said you checked the coil packs, right?

Then you could look at the injectors. Remove and clean.

Sometimes just the throttle body is stuffed. Can you borrow one from someone to swap and see if it makes a difference?


hey man i appreciate all the help

ive done the spark plugs and also tried to play coil swap but have ordered a descent coil testing tool another week or so.wait for it and have got a dozen oem coils from wreckers.

but I'm still having issues like it comes and goes it really needs heat soak for it to idle rough as in after a good 40km drive in the cold its now 15C days

but the thing is i don't think its ECU

i have 2 spare throttle bodies need to buy a gasket to try but my scan tool showed correct readings for open and close as well as at the pedal at one stage it didn't show correctly but now it has haven't checked it recently though

I have done the PCV valve mod it was totally clogged so glad my intake etc is now cleaning it self up slowly as the plastic piping was all oil-filled now it burns NO oil whatsoever

before the dipstick was going down each tank full by half a litre

Also its running 15/40 oil with a mix of 20/50 added in to thicken, could it be a touch to thick i thought the engine was worn but it isnt as bad as i though

no codes on scan tool

i am baffled at why its doing this .
 

Sliding_vt

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I have also replaced the fuel filter was pretty sludged as i cut it open

i also have swapped the valve the purge valve to no help on fixing the issue also and put the org back in

i think if i got time tomorrow I will do an oil and filter change already done 2 changes oil to 1 filter in under 3k km as its pretty dirty but popping the valve cover off it wasn't all that sludged especially for a completely blocked PCV valve but it could use lots of oil changes as its been done every 10 k km by the previous owner

i have also taken all six injectors out and had them flow tested they were perfectly fine all balanced by a single percent

until i got a decent coil testing tool or use my scope on them playing coil swap is useless to find if 1 is mis firing
 
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wannaeatyourbrains

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Did anyone say crank angle sensor? Tis the season for them. Happening when it is hot and all. You can buy 5 of them for $10 off Alibaba. Part number is 12582652. You'll know why I say that when you look at the price on eBay.

Should be 5W 30 oil as per the manual. They don't like anything else.

There is another filter in the sender unit you can check when all else fails.

And what about your air filter? Is it in good condition? They don't like a blocked air filter either.

And the camshaft sensors and solenoids.The actuators. Couldn't hurt to rip them out and give them a tub. Especially if the position sensors have sludge, or the filter bits are filthy, it can cause rough idle. Makes me wanna tub mine just thinking about it.
 
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Sliding_vt

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Did anyone say crank angle sensor? Tis the season for them. Happening when it is hot and all. You can buy 5 of them for $10 off Alibaba. Part number is 12582652. You'll know why I say that when you look at the price on eBay.

Should be 5W 30 oil as per the manual. They don't like anything else.

There is another filter in the sender unit you can check when all else fails.

And what about your air filter? Is it in good condition? They don't like a blocked air filter either.

And the camshaft sensors and solenoids.The actuators. Couldn't hurt to rip them out and give them a tub. Especially if the position sensors have sludge, or the filter bits are filthy, it can cause rough idle. Makes me wanna tub mine just thinking about it.

ya these crank angle sensors are pricey but wouldn't that give me issues during driving to?

really this fussy ? i am planning on some 15/40 to run on a short interval today im paranoid on sludge due to its just had the plain 10k to 15k changes

air filter brand new

ya those sensors i might have to give them a tub down

also what do you mean by a filter in the sender unit ?
 

Sliding_vt

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ok

i did a oil change to straight 15/40 and seems to have no codes still!

only code was a heater to a 02 sensor just cleared it but might have a spare from my wide band kit for tuning

won't be able to do much to coils have played coil swap with no luck though but will be better with the tool iive bought to measure data

i must admit its nice to have clean oil when i did the first 2 changes when first owning the car the oil went to black ash instantly this time its clear but for how long :)
 
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