Prado 120 issues - seriously dangerous and cant find issue

pradojay
I'm new, be nice!
Posts: 2
Joined: June 20th, 2015, 12:35 pm

Prado 120 issues - seriously dangerous and cant find issue

Unread post by pradojay » June 20th, 2015, 12:44 pm

Hi Guys... Jay from Perth here. I've had my Prado for a few years now and I've had an ongoing and continuous problem. I'm desperately hoping for some advice/guidance here.

Essentially our Prado (Turbo Diesel, D4D 2008 model, 8 Seater) cuts out periodically.. Sometimes at a traffic light and sometimes while driving (last night it cut out at 100kph on the freeway, at night, in the rain, with my wife driving it which could have been absolutely disastrous - luckily she pushed it into neutral and managed to get it started again by the time it slowed down to 70kph... but this with no power steering or brakes!). This happens fairly infrequently (2 or 3 times a month) and it leaves no trace on the computer for technicians to find. We have had it back to the dealers (Toyota) numerous times (each time costing around $800) and they have never been able to find the issue. Last time they had it for 2 weeks and drove 280km with it without it happening once (that was 6 months ago and we have had the issue several times since then, culminating in the serious issue last night).

If it cuts out at a traffic light the characteristics are a slight decrease in RPM while at idle (from about 800rpm to about 650rpm - this after about 15 seconds of coming to a standstill) and then an abrupt stall. It starts on the first attempt after about 3 seconds and then appears normal for a few more days or weeks. Periodically we will have a significant loss in power on takeoff (this is infrequent - about once a month) - this again is seriously dangerous.

Like I say, Toyota cant find the issue - to me it sounds like fuel, but I cant figure out why it would go for such long periods without any issues. We have bought a deep cycle charger to see if it could be the battery/electrical - to no avail - not sure if I should try changing the battery, although we did change the battery about 2 years ago and that made a slight difference (went about 3 months without any issues, then back to normal) so I dont know if that was coincidental or not.

We've been so frustrated by this issue (it's been ongoing for over 3 years now) and now have to consider selling the car as I cannot have my wife driving it when it cuts out (its an accident waiting to happen). However I also feel very strongly about giving the car to someone else with such a safety issue on the go.

Does anyone have any advice on what I can try... The car leaves no fuel stains on the floor (so fuel pipe sucking air sounds unlikely)... Looking for any help.

Thanking you guys for any advice
Kind regards
Jason

mydmax
Need to get out more
Posts: 5384
Joined: August 4th, 2011, 10:43 pm

Re: Prado 120 issues - seriously dangerous and cant find iss

Unread post by mydmax » June 20th, 2015, 4:45 pm

I would look for a temperature related item. ie, something which sometimes goes cranky after it warms up. If it doesn't happen when cold, the Crank Angle Sensor would be a good thing to have replaced, (if not too expensive), or a substitute CAS to try to prove it is or isn't the problem. Seeing you have had it to the Delayer many times, they may fit one if prepared to buy it when all is well again.

It is possible to have no stains on the floor BUT the fuel lines are dragging in air to the system. The small primer pump on the fuel filter housing is usually the culprit there. It may be faulty.

Rather strange the delayer can't find the problem. They are the experts of their own brand "apparently".

pradojay
I'm new, be nice!
Posts: 2
Joined: June 20th, 2015, 12:35 pm

Re: Prado 120 issues - seriously dangerous and cant find iss

Unread post by pradojay » June 21st, 2015, 1:00 pm

Thanks Mydmax... yeah, I have been pretty frustrated by the dealers lack of ability to find (or even make a good guess at) the issue. I have posted on a few forums and the consensus coming back is that I need to get it over to a diesel specialist (not to the Toyota guys who only really do superficial stuff in line with regular servicing).

Thanks a million for your advice - I will take a look at a substitute CAS and will double check the primer pump... I just hope that i can get it sorted. I (and the family) love the car... definitely don't want to get rid of it.

Cheers.
Jay

stanmiko
I'm new, be nice!
Posts: 3
Joined: October 14th, 2015, 10:58 am

Re: Prado 120 issues - seriously dangerous and cant find iss

Unread post by stanmiko » October 14th, 2015, 11:26 am

I had a similar issue with my D4D 120 Series... rough idle and stalling. I finally pinpointed the problem as being an "unserviced" MAF sensor.
2 x small screws removed it...several sprays of CRC MAF Sensor Cleaner...allowed it to dry for a few minutes and presto! Problem solved. Smoother acceleration, no more rough idle, no stalling. Plus slightly improved fuel consumption.

Return to “Prado”