Hi all,
My car has a serious problem. Any tune up boys in the house?!
PATIENT:
Volvo480 turbo. Power curve 6 months ago on rolling road showed a standard torque and power curve form, peaking at about 130bhp at 5200rpm. Nothing has been changed except the exhaust which was replaced after grounding out on a tree stump. The CAT has been removed. A power curve run this morning was booked to create a snapshot prior to any further work. I was expecting maybe some boost creep after 5000rpm, instead l was told the car has a serious loss of power issue.
SYMPTOMS: comparing the two power graphs.
TORQUE:
Normal shape up to to about 3000rpm. Dropping sharply after this and never really recovering except slightly after 5000rpm.
BHP:
About 10% lower than before up to 3000rpm. It then goes down and plateuas around 40 - 50 bhp LOWER than before and only picks up to after 5000rpm to finish at 101bhp at 5800rpm. Hmm nice.
BOOST:
Comes up to 7psi (as intended) but start to fall away to 6psi btween 3-5000rpms recovering to 7psi agin after 5000rpm.
Other symptoms:
Idle problem. When out of gear it hunts/chases momentarily although this is intermittent in how much it does this. (Wavering idle thread)
I haven't been thrahing my car of late so as the problem isn't noticeable up to 60mph l was initially suspect about the readings.
However l have since found a private straight where l ran it to 110mph, and have been able to sense the hesitation after 3000rpm (on the same straight the car would pretty much squirt to 125mph without problem.) The turbo guage also reflects what the rolling road curve has shown.
Initial suspicions.
LAMDA sensor: Damaged by the exhaust fitters, it may not be sending a reading or is stuck at one particular reading.
POINTS: I know that the 480t can run like a dog if the wrong points are used. (I will be checking these over the weekend to see if they are the right ones.)
The tuner said that this wouldn't be enough to cause this problem but the LAMDA might?
Additionally the tuner suggested:
FUEL LINE: unlikely as it picks up again after 5000rpm
BOOST CONTROL: OK so it loses 1 psi after 3000rpm but that would account for up to 50bhp loss! More likely this is a symptom rather than the root cause.
IGNITION TIMING: The engine is falsely reading high charge temperatures and retarding the timing. This could be faulty ECU, or sensors.
TURBO itself. Does'nt smoke or make a noise. But it is not unknown that a turbo could be hitting the sides of the housing at certain revs, creating a flow resistance but spinning correctly at higher or lower revs. Sounds plausible but with no noise or smoke this is less likely but not impossible.
Car is going in tuesday for diagnostics, but this could turn into a money pit if it proves hard to find. I am tempted to rip out the intake manifold (cracked?), turbo, lamda etc... and replace as much as l can with spares and salvage.
I don't expect an exact diagnosis, (unless anyone has had this before and just 'knows') but eliminating a few possibilites or suggesting a few tests l could do to narrow it down would be great.
I am absolutely gutted at the moment, sob.
Thanks for reading,
Dan
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"POINTS: I know that the 480t can run like a dog if the wrong points are used. (I will be checking these over the weekend to see if they are the right ones.)"
No 'points' on this car!
I reckon the exhaust monkeys have screwed up the lambda probe
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Points?
Again another of my mis-interpretations. I call sparkplugs points? What are then, a diesel thing? I have looked at the points er...l mean sparks (lol l just typed that!) and they are not the optimal ones, Bosch NGK-R BP5 instead of BP5ES. I'm not sure this is the root.
Do you think the lambda could be the fault? Does it miss its cat, the poor thing? Well immediately after they changed the exhaust it was chasing/hunting continually when l took it away (first junction and ooh what the hell?). I went back and they unplugged the LAMDA and plugged it in again. The hunting went away but they were very surprised it would cause that. (I didn't pay them peanuts either!)
Perhaps its been mashed ever since then? I never would have thought and l'm sure l noted the extra responsiveness once they removed the CAT immediately but I suppose you could gain responsiveness but have less power overall...hmmm, one to note down.
Why does tomorrow have to be sunday? I want my horses back..*throws toy from pram*
dan
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This may or may not be relevant but you mention a drop off of power or hesitation at 3000 revs. Could you describe this as a "flat spot?". If so, it might be interesting to note that on the Fiat Cinq Sporting a "flat spot" at 3000 revs is a well documented sign of a duff Lamda. Previous contributor could well be right in saying that they screwed up your Lamda sensor.
Will be interested to hear the outcome of this one.
Rgds.
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Why do Fiats tend to eat Lambda probes? Every time we have one in with the EMS light on it's always the Lambda sensor up the swanny!
Bosch Sensors used on FIATS [IIRC...] which are used in most other Euro cars too so why the problem? Or is it typical FIAT build quality??
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Good question, to which I too would like to know the answer.
What about vibration patterns ? When you find out, please let me know. Thanks, petel@clara.co.uk
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Are you my Dad, Pete?
My dad is Pete L, too :)
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I can assure you that I am not your "Dad" Dr Dave but am I right in thinking that you live in the Taunton area ?
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Hey, Dr Dave.
You say every time you have a Fiat in with the EMS light on, it is always the Lamda "up the swanny."
In your experience, is this all Fiats or just the Cinq sporting?
Rgds. petel@clara.co.uk
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Oh yes Pete - just outside Taunton, in Cider Country!
I've seen the EMS light on Puntos (not just confined to the sporting model) - and every time it has been the Lambda Sensor.
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Hello Dr Dave.
Thanks for the confirmation re the Lamda sensors.
Can you please advise, when you change the sensor for a new one, does the ECU then have to be reset ?
I am in Yeovil by the way.
Thanks for your help. petel@clara.co.uk
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So my LAMDA sensor is causing 30-40% drop in bhp across the range? I bought another today but l can't fit it as the connectors are wrong even though its the correct adaptor (growl).
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You must have bought a universal sensor, Dan?
Not ideal but much much cheaper than main dealer prices!
Some deft soldering and adaption of the harnesses may be called for..
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Pete - after fitting a new Lambda sensor, no ECU reset is necessary. The whole purpose of the Lambda sensor is to provide a closed loop feedback signal to the fuelling system to ensure a clean, efficient burn.
Oh - it's a small world, isn't it - you being in Yeovil :)
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Hello Dr Dave.
Thank you for the confirmation re the fact that ECU reset is not required after change of Lambda sensor. Note, I spelt "Lambda" properly this time.
It is a small world and hope to have a long chat with you one day. Sorry to hear that a sensor change did not solve the problem for Dan. Rgds.
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Well its the right one for the model. Cost me £50, so l don't want to know what a main dealer would charge!
Looking at 480 sites it appears that the Lambda will effect the ECU's ignition and timing as it attemts to get a cleaner burn. If the LAMBDA's gone awol then so does your performance.
Frankly l'm all for ripping the *&^%$£" out completely and putting in a mappable ECU that doesn't care if you got flames coming out of your exhaust!
dan
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Well it's not the LAMBDA. £60 down. Worth a try l supppose, now all l got left is mister rolling road and £XXXX later....
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Mmmmm sounds sick dunnit?Without seeing it I wouldn't like to hazard a guess but it might be worth checking the earth points on the rear of the inlet manifold at the timing belt end. Common failure on these cars which can cause all sorts of problems, Do you have a leak on the pipework/ducting opening up under boost? You may have to run the new lambda sensor for a short while to allow it to 'fire up' properly. (not usually a problem with oe sensors)
Interesting topic though!
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Woah, fire up? That'll be the something new l learned for today!
I drove about 80-90 miles at various speeds. Would that be enough?
Currently popular possibilities are:
1)Inward leak between air meter and turbo and running lean.
2)Failing fuel pump or failing/blocked injector(s). I'm not sure this fits the patterns though.
3)ECU. Er.. enough said.
4) "...it might be worth checking the earth points on the rear of the inlet manifold at the timing belt end."
I will definitely have a look. A few months back the "bulb out" light came on permanently when ALL bulbs were working. (I checked frequently) and the day running light (which was always on EVEN when day running bulbs blew) went out. This light has never come back. I recall this occured when l grounded the car engine/exhaust on a tree stump.
Could this be symptomatic of a short caused by detachment/damage to these earth points? (or others??) If this is the case and that can cause engine management problems this may be it. This also brings to mind a paragraph from the Haynes manual as l clawed at every straw:
Roughly "..the engine management can enter a back up or safe mode, this mode is so sophisticated (sic) that the driver may not even be aware of the change"
Ack, now l can't wait to get my car back from the tuners and find out!
Regards,
dan (BTW hope this isn't a duplicate - last one vanished on me)
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OK. Tuner people have done the business and reckon they haven't missed anything.
1)Wastegate is weak and opening at 2psi.
2)Alternator is on its way out, current isn't steady.
3)There is an air leak (resonably large) on the intake side of the head...somewhere.
No fixes made, just investigation. 3) is a pain but l think a joss stick bundle in a still garage may be able to locate it.
The wastegate should be straightforward. As for the alternator, any suggestions as to what's best: new oe, new aftermarket (partsco), recon? (obviously oe but is it WORTH it?) The tuner said go to Bosch for recon, he wouldn't recommend anywhere else)
Bill: £105 If this is everything then l think that's well worth the money. (To think l spent £50 on an unecessary lambda change doh!)
cheers,
dan
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"Wastegate is weak and opening at 2psi"
b***** hell! I reckon DJW's tractor goes better than your car!
"There is an air leak (reasonably large) on the intake side of the head...somewhere"
This has to be your 'problem'. Inlet manifold gasket, perhaps?
"As for the alternator, any suggestions as to what's best"
Recon alternators seem to be a bit of a lottery (IMO) I've had ***** recon units, once fitted make more noise than the old unit!
You pays your money and takes your choice, Dan :)
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Lol, l still can't believe l was driving around with a crippled car and l didn't even notice until l had it rolling road checked.
How embarassing!
Now of course l am looking forward to getting those nags back, do you think my joss stick method would work to locate this air leak?
dan
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Garage must think l'm made of money...
New wastegate £140 before fitting! Aargh!
New alternator £140 before fitting! Aargh!
Inlet gasket change. £100 including parts and labour. Arr..not so bad that one.
Hmmm think l'll source this elsewhere cheers...call Mr supersalvageman.
Alternator (96) checked and sent £45 hurrah!
Wastegate £15 Mega-Hurrah!
Turning up tomorrow by courier, hurrah!
dan
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Aslong as the parts are serviceable, Dan!
Fingers crossed, all will be well very soon :-)
Don't forget, if you are fitting the wastegate yourself (??) it will need proper adjustment, it's not plug n' play
I don't know if the garage in question would be happy fitting used parts?
Can sometimes be more of a pain in the backside from a garge point-of-view :-(
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I've said l don't expect them to guarantee the parts and given the amount of money they've had from me already, and future works lined up (head swap, bodywork restore etc...) I think they can't really complain.
The parts will be in good working order and they make their money on labour so everyone's happy. Booked in for tuesday.
Fingers crossed,
dan
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RESULT!
Three days in all. One extra day because volvo failed to deliver the two gaskets required for the job, like what are you supposed to do with one? And another day's delay when l was called and told that it was impossible to do the job (removing the turbo proper) without either:
a) taking the head off the engine.
b) moving and tilting the engine forwards!
£250 in labour and l got my bundle of joy back today. It's great - like having a new car.
Unfortunately this lesson: "You cannot renew the manifold gaskets on the 480 turbo without excessive labour due to the positioning of the engine" cost me £250 and will be of no use to any of you!
Only person other than me to ever have a 480T on this forum was Andy Sampson and he got hit by a piece of Russian satellite... ok... he sold his 480T and is probably now driving round in a Golf or something equally inspiring.
bitter, nah
dan
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Hey, whats with the russion satellite?
Still got my 480 Turbo, Sorted all of the probs with it now and must admit bar the silly cloth parcel shelf it has got to be one of the most fun cars I have owned (In-between the 200hp RX7 and Mk 2 Golf GTI 16v)
And strangly the styling is growing on me now!
Just passed the 122k mark and it doesnt use a drop of oil, and every bit of electrical kit works!!
Would get rid of it this year but they are not worth more than 2 bob so may as well keep it for a while, shame cause i'd luv a new project, then again I keep seeing the old 3ltr Turbo Supra's for sale - Hmmmmmmmmmmmmmm
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Ah you're alive!
Never did find those connectors you were trying to figure.
I take it you just fixed it up to stock and had some attempt at selling. (I saw your ad on another site somewhere).
How much did you want for it anyways?
Dan
P.s. Right about the Golf though wasn't l, lol! ;)
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