[Loxley64]

Hi,

Hard to describe this problem in technical terms, but here goes. My girlfriends 96 Rav4 ( 65,000 miles, serviced every year since new ) has started to 'play up'. I haven't driven it myself since before the winter when it was as good as always, nice smooth drive, easy throttle response, no problems.

At some point over the winter something has happened. Most of her driving is around town so with 'crawling' speeds of 15-25 mph on average it's hard to tell how long it's been going on, but now, either hot or cold, the throttle will respond intermittently. You can get in from cold, turn it on and take off no problem, other times it's a struggle to get it up to 30mph. It 'chugs' or jumps as if firing on only a few cylinders, but then you floor the pedal and it races off no problem. I haven't managed to get it over 60mph though it used to hit 70+ easily.
Fuel economy has dropped due to having to floor it to get any real throttle response rather than cruising it.

It really is a hit and miss problem, it doesn't like to idle at all, if you take your foot off the pedal then the power drops off more or less immediately.

I have changed distributor cap, rotor arm and spark plugs. It's just gone through the MOT 2 weeks ago so no notice then of emmissions problems.

Any other ideas as to what to change / check / alter or do i risk taking it to a toyota dealer and getting it professionally checked out ?

Suggestions ?

Cheers
Mark

 

[Pim]

Have you cleaned the throttle body already and checked if that resolved your issue?
Here is how to do it.
Greetz

Pim

 

[Ken Allistone]

Check the EGR valve, with the engine running put your hand over the EGR valve and feel underneeth it, then rev the engine, the EGR should only open above about 2000 rpm, if your's is opening all the time and getting wider and wider you will be able to feel it.
If this is the case then the EGR VSV needs replacing, if so then read JLC's post just ablove this one and read how to do it.
Good luck.

 

[Loxley64]

Hi Ken and Pim,

Thanks for the tips. I see someone else has an identical faulty to mine, so is this a common fault on these Ravs ?

http://www.rav4world.com/forums/85-4-1-faults-fixes/83536-jumping-no-power-problem.html

I did look for a set of HT leads on the internet, but how do I determine what set to buy ?
Mine is a 1996 year registration but isn't necessarily a 96 model. Is there anything on the chassis which will denote what specific one i have ?

I will try with the valve clean up exercise and see if it helps also.

Thanks
Mark

 

[Ken Allistone]

Plug/HT leads are a common problem with this model, the insulation brakes down on the part that goes down inside the head and onto the plug, you cannot see it arcing.
I still have a problem with hesitation at around 2000 rpm - another very long story, the first thing I replaced to try and cure it was the leads - no luck for me and the originals after 12 yrs and 70k miles were probably still just as good as the new ones I bought, however I have kept the new ones on and they are fine.
As you are also in the UK, go to Euro Car Parts, they have several types I know, you need to look and decide if you have a distributor or not - you probably do - in which case you get 5 leads not 4. If you don't then you need to look at the ends that connect to the coil packs (may also be the case if you have a distributor too) and determine if they are straight or angled connectors. Once you have done that you will be able to tell ECP what you want, they usually have a set or two on the shelf and in my case they checked them for me first before I collected. They also deliver foc.
Whatever you do, don't buy Bosch, I know they have a good reputation but not for Rav leads!!
If you can afford it, go to Toyota, word of warning though, they only sell leads with plugs and when I enquired the cost was way over 100 pounds!!

 

[hd72m]

2nd do not buy botch wires!

 

[Mick Hatzo]

Is there anything on the chassis which will denote what specific one i have ?

Write down your VIN number and copy it in the following page:
ToyoDIY.com

It will immediately identify your car and give you some details about it: Month/Year, Color, Body type etc.

The VIN number is a 17-digit sequence of letters and numbers (ex: JT171**********) and it is stamped on a label in the engine bay (facing the car's opened hood, upper side, dead center, just below the vent that provides with fresh air the climate control system).
And as my useless depiction of the actual placing may mislead you, I believe the VIN number is noted in the registration papers of the vehicle as well.

 

[Raving Man]

I'm getting into crank sensor replacement and cleaning the crank timing gear related to the crank sensor.

Apart from the wires, it could be the throttle position sensor.

On the earlier ones, the pick-up coils inside the distributor sometimes need to be replaced.

Make sure the distributor is bolted in properly, and doesn't have a loose distributor bolt.

On pre-98 models, they are all the same, so don't worry too much, it's when you get to 98 that the ignition system changes, where there is no distributor, where we have twin coils instead.

Might be worth doing the fuel filter and air filter if they haven't been done, but sounds like an ignition problem.

Fuel pump or fuel pressure regulator shouldn't suddenly give such variable running, but my mechanic says that my fuel pressure regulator was stuck closed when he had a look at it when mine wouldn't start.

Lambda sensor can give such variable problems.

Unfortunately it's a bit of a list. It is always worth getting it checked for codes, but then you get into part replacement based on theory or you have to use proper diagnostics.

The temperature sensors - engine coolant sensor is a weakness, can be checked using a mulitmeter - read their resistances, but the coolant sensor is the major one of these two.

 

[hd72m]

Raving Man what is this? "Lambda sensor."

 

[Pim]

Lambda sensor is the same as your O2 or Oxygen sensor.
Oxygen sensor - Wikipedia, the free encyclopedia
Greetz

Pim

 

[hd72m]

Thanks.

 

[Raving Man]

I never knew they had them for diving equipment.

 

[Pim]

Oh they even have oxygen sensors for water treatment and aquarium usage.
But those are different from the car versions offcourse.
Greetz

Pim