Omega Owners Forum
Chat Area => General Car Chat => Topic started by: Webby the Bear on 19 December 2012, 01:31:26
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Disclaimer.... this thread is not about the diagnosis, treatment or the adverisments of products for erectile dysfunction. I know we're all getting on but really... see your GP if that's the case ;D ;D ;D ;D ;D ;D
ANYHOOOOOO
I have recently been looking in to overcoming performance problems and I thought I'd pass on what I've learned and perhaps spark (no pun) debate or discussion on what to do if you encounter such trouble. It also may be worth noting that these are helping to diagnose whats wrong if there's no check engine light. Obviously if you have a fault code then you can get that read and at the very least you know where to start from. But this is mainly for the home DIYer with no codes :y
I think first of all that the mantre here should be not to neglect the basics, and as you go and change/do something it's really important to test over a period of time the effects your change has had on the performance so you can say that solved it, that helped a bit or that did fek all. Narrowing down your problem... I'm getting well in to diagnosing stuff ;D ;D ;D ;D
Ok, so first the basics that anyone can do would be:
1.) Check and replace your spark plugs. I find that if I'm pulling out plugs I like to keep them in order so when they're all out and if I see something not right or inconsistent with one of them I can start to narrow down a potemtial problem to a particular cylinder.
2.) Test (if possible) and replace your fuel filter. If you have a fuel pressure gauge you can test the pressure going in to and coming out of the filter. If this is restricted in any way this can cause a problem . There could be a blockage affecting the volume of fuel getting to your emgine. Replace it. Tis a serviceable item anyway.
3.) Air filter. Again, serviceable item. Chuck a new one in.
4.) Vacuum leaks. You may have heard me mention ETCG before. I love the guy and have watched all his videos. Here's one for this procedure which I like... http://www.youtube.com/watch?v=9CPqbaSgcok+
5.) Ignition Voltage Leak. My understanding of this is that if two or more HT leads are bunched up close to each other that this can cause problems. You may also hear sparks jumping about. You can soak the leads in water and try and try and worsen the problem to make it more viewable. This I'm a bit unclear on so if anybody out there can give us some tips on finding ignition voltage leaks go for it :y
6.) Power balance test. I've never done this and it probably would be difficult on the V6 but this would be pulling out each HT lead and listening for the engine to drop RPM. If it doesn't you have found the cylinder that's affected and you can check for spark, do a compression or leak down etc etc
Ok, so those above anyone can do. The next things involve certain tools......
7.) Compression test (or even better...leak down test). it stands to reason that if you have a loss or lack of compression youre going to be down on power. performing these tests will clue you in to finding out if you have a leak and with the leak down where its coming from. I'm actually going to persuade and threaten if necessary ask my school technician nicely if I can borrow the compression tester for home. (I actually believe I have a bit of a performance prob so I am covering every angle... whilst most importantly learning how to use the tools comfidently without having to be baby fed)
8.) Scanning tool. the lovely folk on here offer their services. if they do a full scan they can look at all sorts of readings that could key you in to a particular problem.
I hope this may be of use. if ive got anything wrong please say (in a nice way :)) and add your wisdom :y :y :y
one question i have myself is this.....
Someone I spoke to mentioned a fuel injection problem and with the car being quite old there could be a build up of shite in the cylinders and the fuel injected having a sponge effect. it was mentioned that injectors should also be serviced. thats fine too. however what could i get to remove the build up of stuff in my cylinders. is ''Engine Flush'' the thing we're talking about here?
Just whilst talking about that if anyone has anything to add on solving the problem if its fuel related would love to hear your thoughts.
cheers chaps.
Car Bear
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Webby there is a method called carbon clean which I tried in the past .. they disconnect the fuel hoses and connect the cleaner apparatus instead.. it cleans all the path that the fuel travels through but..
but I dont recommend for cars old or with high mileage (say 100 K Kms) because the valve and gasket deposits erode non uniformly and start to leak..
and for the injector cleaning , same rule applies.. old cars is a definite no no because those injectors can easily start to leak and you cant find which one in any pressure leak test easily .. instead I recommend flow pattern test and change the faulty injectors with a new one.. this is my what bad experiences teach me.. :y
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and I forgot to say, thanks for sharing this useful post Webby :y :y :y
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The best way to look for HT lead problems (instead of water) is to run the car in the dark and look under the bonnet for the arcing leads ;)
Generally, if the car is a little sluggish (and there are no fault codes) then the first point of call should be a good service, then start looking for other issues if it isn't sorted :y
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Now, back to the Erectile Dysfunction side of the thread Webby.........Any chance of a 'Howto' :-\ ;D :y
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Webby there is a method called carbon clean which I tried in the past .. they disconnect the fuel hoses and connect the cleaner apparatus instead.. it cleans all the path that the fuel travels through but..
but I dont recommend for cars old or with high mileage (say 100 K Kms) because the valve and gasket deposits erode non uniformly and start to leak..
and for the injector cleaning , same rule applies.. old cars is a definite no no because those injectors can easily start to leak and you cant find which one in any pressure leak test easily .. instead I recommend flow pattern test and change the faulty injectors with a new one.. this is my what bad experiences teach me.. :y
nice one cem. what exactly is a flow pattern test? like a scope trace on the fuel injectors to see their performance? presumably then if you find a bad 'un thats the one to replace? :)
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The best way to look for HT lead problems (instead of water) is to run the car in the dark and look under the bonnet for the arcing leads ;)
Generally, if the car is a little sluggish (and there are no fault codes) then the first point of call should be a good service, then start looking for other issues if it isn't sorted :y
nice one lazy. i suppose if you own a v6 like me its going to be hard to see as the wires go in to the murky depths behind the block.....if not water is there anything you can do to see this more easily? :)
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Now, back to the Erectile Dysfunction side of the thread Webby.........Any chance of a 'Howto' :-\ ;D :y
hahaha definitely. walk round with a breezeblock tied to it... thatr should promote good blood flow in to the old boy.
if not a splint of some form..... match stick right up to fence post ;D ;D ;D ;D ;D
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Now, back to the Erectile Dysfunction side of the thread Webby.........Any chance of a 'Howto' :-\ ;D :y
get the wife to blow it up ;D ;D:-X :-X
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whilst i think of it cem.... could you recommend a decent place to get the injector test done? or does anyone ekse have experience of this? obviously replacing an injector is quite straight forward :y
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Webby there is a method called carbon clean which I tried in the past .. they disconnect the fuel hoses and connect the cleaner apparatus instead.. it cleans all the path that the fuel travels through but..
but I dont recommend for cars old or with high mileage (say 100 K Kms) because the valve and gasket deposits erode non uniformly and start to leak..
and for the injector cleaning , same rule applies.. old cars is a definite no no because those injectors can easily start to leak and you cant find which one in any pressure leak test easily .. instead I recommend flow pattern test and change the faulty injectors with a new one.. this is my what bad experiences teach me.. :y
nice one cem. what exactly is a flow pattern test? like a scope trace on the fuel injectors to see their performance? presumably then if you find a bad 'un thats the one to replace? :)
something like these.. their spray pattern must be uniform (ie not angled or pissing like) and in a specific time period the fluid amounts must be equal..
http://www.youtube.com/watch?v=hxWpYr6yMaM (http://www.youtube.com/watch?v=hxWpYr6yMaM)
and leaking injectors not that easy to spot ;D
http://www.youtube.com/watch?v=Y2l0L8B4J-g (http://www.youtube.com/watch?v=Y2l0L8B4J-g)
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couple of things i would add,
clean the throttle body both sides of butterfly, amazing what a difference it makes when not covered in oily residue,
not sure if this is applicable to v6 but on the straight 6,cleaning the crank sensor end made a hell of a difference to smooth running,as you know they are magnetic and tend to pick up small bits of magnetic dust etc to which an oily gunk can stick, thus impairing the signal,these to small jobs always made the car whcih although ran ok seem to run just that bit smoother and more perky :y
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did you monitor the lambdas they may be lazy..
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
any tech 2 around you can give the answer in a minute.. :) :y
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
any tech 2 around you can give the answer in a minute.. :) :y
Thanks Cem,
I did all the things that TB told me to do that could affect the laziness of my o2's. the only thing i havent done is ran the car without the maf plugged in.
if i do this will i perhaps see an increase in performance hence signalling my MAF was bad?
if i then do that and the car still runs bad from cold start i'm thinking the O2 sensors themselves should be replaced.
what do you think?
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
any tech 2 around you can give the answer in a minute.. :) :y
Thanks Cem,
I did all the things that TB told me to do that could affect the laziness of my o2's. the only thing i havent done is ran the car without the maf plugged in.
if i do this 1) will i perhaps see an increase in performance hence signalling my MAF was bad?
if i then do that and the car still runs bad from cold start 2) i'm thinking the O2 sensors themselves should be replaced.
what do you think?
1) the answer depends on the default map of ECU.. if the default map is prepared with a higher temperature (than your current temperature) ecu will inject less fuel than required .. in reverse case ecu will inject more fuel resulting with rich mixture..but as the lambdas make secondary correction, performance wont be different imo.. unless the lambdas are donald..
2) when you monitor with tech 2 ,you will see lambdas shifiting between 0-1.0 volts .. if slow they require changing.. however
http://www.lambdapower.co.uk/diagnosis/diagnostic_index.asp#q1 (http://www.lambdapower.co.uk/diagnosis/diagnostic_index.asp#q1) recommends 70K or 7-10 years as official lambda change interval ..this means you have to change them anyway ;D
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
When cold, its open loop, so no.
*Unless the trims are well out*
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
When cold, its open loop, so no.
*Unless the trims are well out*
I assumed not cold.. hot..
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
When cold, its open loop, so no.
*Unless the trims are well out*
I assumed not cold.. hot..
Me no understumble :-[ ??
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did you monitor the lambdas they may be lazy..
That's an excellent question Cem.
One thing I have noticed is that the car from a cold (even colder now we're in winter) start really has no performance at all. after it warms up its good.
could this be a performance problem relating to those lazy lambdas?
When cold, its open loop, so no.
*Unless the trims are well out*
I assumed not cold.. hot..
Me no understumble :-[ ??
me too ;D I thought (assumed ;D :-[ ) you commented on my post .. and I explained the assumption but you commented on Webbie ;D
too much programming makes me like this ::)
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too much programming makes me like this ::)
You should try adding 453 LUNs to a handful of servers. I've gone number blind now ;D
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too much programming makes me like this ::)
You should try adding 453 LUNs to a handful of servers. I've gone number blind now ;D
everyday I ask myself a question.. can I retire before someone drop me in cemetery :(
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Evening chaps,
I'm gonna be honest I can't remember if the trims were well off when we TechII'ed it.
I found this page which gives a list of the sensors that are used in the power train...
http://www.freeasestudyguides.com/fuel-trim-adaptive-learning.html
The sensors are these:
(http://i1226.photobucket.com/albums/ee402/webbybear1/pcmsen_zps568d755f.png)
Ok, firstly everything is easy to check or replace but...
1.) Does the omega have a TPS? Am i being stoopid? lol
2.) ignition module... is that the disspac?
3.) Is the AIT on the omega the MAF?
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Evening chaps,
I'm gonna be honest I can't remember if the trims were well off when we TechII'ed it.
I found this page which gives a list of the sensors that are used in the power train...
http://www.freeasestudyguides.com/fuel-trim-adaptive-learning.html (http://www.freeasestudyguides.com/fuel-trim-adaptive-learning.html)
The sensors are these:
(http://i1226.photobucket.com/albums/ee402/webbybear1/pcmsen_zps568d755f.png)
Ok, firstly everything is easy to check or replace but...
1.) Does the omega have a TPS? Am i being stoopid? lol
2.) ignition module... is that the disspac?
3.) Is the AIT on the omega the MAF?
1.yes ..it has.. I changed mine .. result was a smoother throttle response..
2.yes.. dispac.. but on new models its not a single unit.. coil per plug instead..
3.yes.. as far as I know.. but never changed it as it showed nearly correct temperatures during tech 2 session..
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Webby, if you have an EGR block it.. but dont disconnect.
coolant temperature sensor is also critical (v-valley under plenum) if it shows incorrect low values , ecu will always inject more fuel causing rich mixture .. but you can understand this from the spark deposits and exhaust..
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Webby, if you have an EGR block it.. but dont disconnect.
coolant temperature sensor is also critical (v-valley under plenum) if it shows incorrect low values , ecu will always inject more fuel causing rich mixture .. but you can understand this from the spark deposits and exhaust..
thanks cem. how do i block the EGR? And will that improve fuel economy and performance? :)
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Webby, if you have an EGR block it.. but dont disconnect.
coolant temperature sensor is also critical (v-valley under plenum) if it shows incorrect low values , ecu will always inject more fuel causing rich mixture .. but you can understand this from the spark deposits and exhaust..
thanks cem. how do i block the EGR? And will that improve fuel economy and performance? :)
very slight decrease in consumption and slight increase in performance.. mostly in hot weather..
however, it -may- disturb your idle when cylinder temperatures go high..
a tiny sheet of metal (usually cut from coke cans) under EGR will block exhaust recirculation into manifold
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Ok, firstly everything is easy to check or replace but...
1.) Does the omega have a TPS? Am i being stoopid? lol
2.) ignition module... is that the disspac?
3.) Is the AIT on the omega the MAF?
Assuming 2.5 v6
1) Yes, its the electrical connector on the throttle body
2) Yes
3) AIT = Air Intake Temp? If so, yes, just above the MAF, on the right angled bit of duct from air filter.
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Webby, if you have an EGR block it.. but dont disconnect.
coolant temperature sensor is also critical (v-valley under plenum) if it shows incorrect low values , ecu will always inject more fuel causing rich mixture .. but you can understand this from the spark deposits and exhaust..
thanks cem. how do i block the EGR? And will that improve fuel economy and performance? :)
ON the V6, the EGR is to reduce NOX. Blocking will have a mariginal affect on cruising MPG, but makes it a bit more sprightly/responsive.
If the EGR is unable to fully close (it will be full of soot and shite), this will make the car run far from optimally, hence the recommendation to block it if the EGR is suspect.
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Webby, if you have an EGR block it.. but dont disconnect.
coolant temperature sensor is also critical (v-valley under plenum) if it shows incorrect low values , ecu will always inject more fuel causing rich mixture .. but you can understand this from the spark deposits and exhaust..
thanks cem. how do i block the EGR? And will that improve fuel economy and performance? :)
ON the V6, the EGR is to reduce NOX. Blocking will have a mariginal affect on cruising MPG, but makes it a bit more sprightly/responsive.
If the EGR is unable to fully close (it will be full of soot and shite), this will make the car run far from optimally, hence the recommendation to block it if the EGR is suspect.
Thanks guys,
I'm going to go down the EGR cleaning route first before I decide to block it off.
I want to get round to testing all the sensors I highlighted above too. I have learned how to test all of them, mainly using a multimeter but unsure if I can check the MAF sensor (in addition to the TechII checks we did) off the car with the multimeter. Any ideas? :y
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Also, just for completeness I'm going to (for the first time ever) replace the O rings to the breather bridge/throttle body. I'm going to also replace the bigger O rings between plenum and inlets...anyone got a part number for them? I'm hoping that just being O rings they'll be pence...but stranger things have happened in the odd world of Vauxhall parts depo!
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ps, just part number needed for plenum to inlet o rings :)