NOT SOLVED: G60 only responds to tiny throttle openings

[G60 Bob 0]

Spent at least 7 hours using the search last night and i think ive found my problem but wanted to get the reasoning behind it.

 

My G60 has just had the lamda replaced with a VAG item but still the mpg isnt as good as it was im down on power and the exhaust is poping on overrun. It seems lke the throttle cable is stiff and seems to be streched so its not hitting the WOT switch when the pedal is fully depressed - actually get better acceleration using a gentle touch of the pedal. I am assuming that because the cable is streched it may not be returning to the closed throttle position either causing high consumption and the odd pop when coming off the throttle.

 

Am i also right to assume that the engine will be running lean because the WOT switch is not being hit and thats why im getting oil temps of 120 degrees just pootling around at 50mph. Why is it so bad not to hit the WOT switch?

 

Does this diagnosis sound about right or can anyone suggest any other possibilities?

[Rustynuts 0]

Change the throttle cable, i think they are only 20 quid, but are a VW only part i believe.

 

Then see how it reacts, process of elimination.

 

For the record i can't see there being a problem, unless the WOT switch is broken and you are actually on WOT. check it clicks when pressed as a starting point.

[G60 Bob 0]

It clicks cleanly both closed and open but the cable and the pedal are very sticky and the cable itself is slack at the throttle body end.

 

Would like possibility explain the hot oil temp due to lean running?

[MattWilde 10]

when my cars timing was seriously retarded i was getting silly oil temps because of the labour to get the thing moving. so overfueling can cause it too.

 

please correct me if i'm talking poo :)

[Supercharged 2]

Have you tried adjusting the cable with the clip? I think there is also a grommet that goes thru the bulkhead that may have popped out...

 

The lambda signal is ignored on WOT (closed loop)

 

Clean the TB too...

[G60 Bob 0]

Checked the cable and its fine hitting both switches its just a little sticky. Im starting to think the timing must be out again as Matt suggested because it seems to rev ok on a very slight throttle but hits a wall as you try to press it any further.

 

The crank pulley was replaced and fitted with a DX bolt about 6 months ago because it had worn the woodruf key - could i have a problem with the crank (or something else) if it has happened again?

[Rustynuts 0]

I think you need to concentrate on your sensors, have you checked the spark plugs for their colour, if they are black it is over fueling, if they are white it i running lean. Make sure that the lambda sensor is earthed properly. Also from what you say it could be that the Cat has broken up and blocking air flow into the exhaust.

 

See how you go with these

[G60 Bob 0]

Vacuum hoses are ok, lamda and blue temp ssensor (both VAG) just replaced, mate mechanic says the crank wouldnt have moved cause of the bolt/threadlock/air gun so im now back to square one again.

 

Will check plugs and timing again when i get the chance - any other suggestions?

[Rustynuts 0]

You need to start eliminating things before we can advise more, thats not meant to sound arsey by the way ;)

[G60 Bob 0]

It turned out to be a blocked/melted cat causing the problem because the exhaust gases cant escape so im ordering a de-cat and full Milltek system from Awesome tomorrow.

 

PLUS it just passed MOT today and after getting the alignment set up and letting the new Konis and H&Rs settle i can REALLY appreciate how good the C handles - the turn in is now phenominal; cant wait to get the power back so that i can test it out properly!

 

One happy (again) Corrado owner - thanks for the help as always.

[_Monkey 0]

It turned out to be a blocked/melted cat causing the problem because the exhaust gases cant escape so im ordering a de-cat and full Milltek system from Awesome tomorrow.

 

That's gonna feel like a rocket when you get it back then. de-cat is always a good idea!

[G60 Bob 0]

Got the exhaust and decat fitted to rule out the melted CAT but the car will still only rev cleanly with a tiny opening of the throttle (i.e. 2 or 3 degrees of travel) any more and its like the engine is being starved of fuel and will not accelerate and the revs struggle to rise. It is also using more fuel than it should be and backfires twice when changing down into 4th and 3rd gear.

 

Timing is 100%, BTS and lamda are new VAG items, vac pipes all new and double checked so im now thinking its fuel related or at least the ECU is restricting fuel as a result of something else. The fuel pump is noisy when starting up even after the filter change and i can smell fuel when the engine is cold (although the fuel smell has always been there)

 

Suspects are throttle switch, FPR, fuel pump and ECU - how can i tell what is causing the problem without throwing more money at the car?

 

please help!