HELP Some input needed for lack of pick-up/power

manisinghb

manisinghb

manisinghb

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Hey guys, been having problems with my 02 Vectra and my mechanic and myself can't seem to figure the problem out. Basically, the car is in good condition and had it since 2008 but recently when I took it for a full service, it just lacks power now. It feels so sluggish and there is absolutely no pick up at all. Local driving is a nightmare as driving in 1st, 2nd and 3rd gears the car just doesn't want to 'move' and the petrol consumption is high. However, at 70,80mph on the motorway it runs like a beauty. My mechanic changed the Fuel Pump relay and the pick up was back again for a few miles only! Then it went back to the no pick up sluggish driving. He now thinks maybe its the throttle sensor? Anyway I don't want to do more work if its only a process of elimination so I thought I could get some input from anyone on here who may have had a similar problem or know the answer?

Also, seems as though the car may be having some electrical trouble, signs appear on the dashboard predominately the ABS sign and a little sign which I think may be the 'servicing' light:

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take it to a vauxhall garage, they will have a better idea. sounds link a sensor problem, though there will be several
 
Well, if fuel consumption is high, I assume the car is running rich. This could mean a lambda, MAF or throttle sensor is playing up (or, as I'm assuming Dogbreath is suggesting, a timing issue). If you are getting other warning lights going on and off, it's possible this could be a problem with the wiring from those sensors, rather than the sensor itself.

It's aprobably less likey, but it could be a knackered temp sensor too. I had the temp sensor go in the TVR and the ecu tried to adjust for the lower temps by enriching the mix. In mine the sensor had gone totally and the temp reading was something like minus 100 degrees and so the car basically flooded itself with fuel. Needed an oil change after as the sump was full of fuel. Luckily it happened when it was in the garage for a service, so Paul could see immediately what the fault was.
 
GODINMAN - yes it was hooked up to the ECU machine which detected a problem with the Fuel Pump relay, which is why it was changed and hence the car drove like a beauty for a few miles before giving up again.

ZAIRS - I think I might leave the dealers last resort, they might charge me a load?

DOGBREATH - yes it has had a timing belt change, do you think the tensioning not being right could be causing a problem?

VOLOSPIAN - that's a brilliant insight, my mechanic did mention perhaps the air intake meter or something? Can't remember what he called it, but it basically judges how much air and temp the car needs?
 
manisinghb said:
my mechanic did mention perhaps the air intake meter or something?
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Yes, that's what I meant by MAF (Mass Air Flow) sensor. Some have MAP (Manifold Absolute Pressure, if I remember correctly) sensors that do pretty much the same kind of thing which is basically to try and detect how much air is going into the engine. This is modified by other sensors (mainly temperature and altitude) to make up for the difference in air density and then the car should calculate the required amount of fuel to inject.

The lambda sensor in the exhaust then checks the amount of oxygen left in the gasses that come out and feed back to the ECU if it's getting the mix right or not.

I seem to remember that the lambda feedback is not used under some circumstances, under acceleration, I think (but may be wrong) and only adjusts on cruise... I'm sure some of the others can correct me on that if I'm wrong, it's a while since I've needed to worry about fuelling feedback loops...

However, if I'm right, it could explain why it cruises OK, but suffers under acceleration as the lamda cuts back the fuel delivery on cruise to the correct mix, but is ignored under acceleration when the car relys upon the MAF or Throttle Position (TPS or Throttle Pot) and RPM reading alone.

If the sensors are out and the car thinks it is getting more air than it actually is, it can end up injecting too much fuel, which results in running rich and losing power.

With the timing issue, if the timing is not correct (maybe something moved when changing the belts) the firing could be retarded, resulting in a loss of power and potentially a drop on MPG as well, as the fuel is not being fully utilised (I'm assuming that's what Dogbreath is talking about...)
 
You can check the MAF by unplugging it, When you unplug it the car will run in a standard pre-determined map and not a learning map. The car should drive reasonably better than you are describing, you will have the fault light on the dash. Other things to check are the Crank sensor the plug is prone to damage and possibly the EGR valve. Presuming its a petrol ?
Best thing to do is get the car on a tech 2 and read the fault codes. A decent garage should read the codes then clear all faults drive the car and then re-read the codes. It may cost £60 but it will be better than changing parts and guessing whats wrong.
 
Some development guys, looked around and the sign of the car with the spanner on the dashboard that I posted earlier suggests electrical faults. My mechanic (one that I can trust) has suggested this also, so will have to look around, spoke to Vauxhall who said that this kind of trouble can lead to excessive fuel consumption and problems in performance. Perhaps because of this the MAF isn't performing properly.
 
Yes that's the ECU's "check engine light" however unless someone experienced looks at it, it won't mean diddly.
 
Took the car to a mate of a mate's cousin, let's just say an acquaintance hehe =D the guy is chief mechanic at Skoda so hopefully can take his word. Basically he plugged in the ECU and looked at the engine hands on, and has come to one of either 2 problems:

1. My car (an 02 Vectra) actually DOESN'T have a air mass flow meter, on my engine the car has an electric throttle sensor (can't remember what its actually called) which basically does the job of air flow and power management for the throttle. He said this (and the gears) in Vectra's is a known problem and may need cleaning out or perhaps changing (which will be costly).

OR

2. Whoever serviced the car and put the timing belt on hasn't put it on properly and hence the problems.

Anyway, would be nice for some verdicts. I am taking the car back on the weekend to get the timing belt checked so we shall see! (Fingers crossed)
 
What engine is in your Vectra..?

When you read the codes you need to delete them first and then re-run the car and re-check, the ECU stores lots of codes and most will be false positives or old codes that are no longer valid.
 
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manisinghb said:
has an electric throttle sensor (can't remember what its actually called) which basically does the job of air flow and power management for the throttle. He said this (and the gears) in Vectra's is a known problem and may need cleaning out or perhaps changing (which will be costly).
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It's called a throttle pot (short for potentiometer) and cost depends on the actual part used. I had a problem with one of the pots in the Cerb and the replacement part was, I dunno, about £25, but pots for the RV8 engined Trevs (chimaera, Griff) are over £100
 
could be throttle body control or more likely i would go for the EGR valve and give it a good clean its a commom thing on vauxhalls and best of all its something you can do yourself for free hope this helps
 
Hi guys, okay the latest:

Checked the timing belt and its fine, my friend said its not as tight as he would prefer it but still fitted properly though. The previous mechanic also hadn't even fitted the negative terminal properly to the battery!!!! =O
This has only left the throttle body. After driving around until the problem kicked in, I took the power cable out of the throttle body, essentially 'resetting it', and the car although not brilliant as usual still started performing better. I'm getting this replaced over the weekend. But I am intrigued in the EGR as pat_1234 suggested. Can u offer a little more advice please, been trying to look around on the EGR but can't seem to find any decent place to locate its actual position in the engine??

P.S. It's a Vectra B 1.6 Club (Z16XE)...

Oh BTW there is a little more trouble in the car that just picked up yesterday and I THINK this may be linked to this 'power' problem. Basically the driver side head light and dipped lights aren't working, the bulbs aren't even blown and the fuses are all fine. Put in new bulbs which also didn't work. The indicators and high beam 'flash' lights are working though. There has been a noise coming from the main light switch area inside the car for a year or so now but never paid attention to it, and today when I was looking at the bulbs I hit the panel of the car and this noise came up again. It was a whirring noise, kind of as though a little pump is trying to start...? I'm trying to link this to my existent problem, could there be a link? Could it be because of the throttle body that the electric circuits are having problems? Or could the actual electrical problem be emanating from the head light area?? Hmmm...?
 
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