engine racing at low rpm

[ganghooks]

Hi all
I have a problem on my SSR-G 2.4 Turbo Auto particularly when cold.
Symptoms when driving slow at aproximately 1000rpm the motor on its
own will jump to around 1600rpm and then suddenly drop to 600rpm
and will continue this cycle. The cycle can be broken by accelerating
but will resume when you back off this will carry on until the engine
warms up a little. Its a little freaky because you can be behind a car at the traffic lights and all of its own it jumps forward so i have to keep my foot on the brake just in case.
I need some help here to find the cuase as this is a safety issue as well.

ganghooks

[hellmett]

Re

Hmmmm!

Maybe sounds like a fault with the "idle up" switch!

Dunno what it could be though, maybe a faulty relay/switch?

Later!

Gary

[phoebelala]

Hmmmm!

Maybe sounds like a fault with the "idle up" switch!

Dunno what it could be though, maybe a faulty relay/switch?

Later!

Gary

I am with hellmett on this one, weired fault! I would start with idle up, cud be its selected but is not working properly. press the button so de-select it and see what happens. you only need it in the sticky stuff and for towing big things anyway.

Al.

[That Ruddy Squirrel]

Could this be due to faulty glowplug(s) ?

Hippo can be a bit lumpy when cold too, but I know her reason


Trev

[sparkyaj]

the plugs on my van are nearly shot now and you can tell with this cold weather.
It starts ok but chugs up and down like mad! restart the pre-heat a few times then turn it over and it works a treat!
Does it do it everytime you stop or just when you start?

[Jezware]

Hmmmm!

Maybe sounds like a fault with the "idle up" switch!

Dunno what it could be though, maybe a faulty relay/switch?

Later!

Gary

From what I remember, the 'idle up' switch only works when in Neutral or Park (on auto's anyway). If this is happening when in gear, I would suspect something else, maybe fueling problems. Does the problem go away when the engine gets upto temp?

[ganghooks]

Definetley not an Idle up problem.

From what I remember, the 'idle up' switch only works when in Neutral or Park (on auto's anyway). If this is happening when in gear, I would suspect something else, maybe fueling problems. Does the problem go away when the engine gets upto temp?

reply(ganghooks###
You are correct. yes it does this while in Drive and also if you slap it in neutral
it is definetly not the idle up, and yes it does go away when the motor
aproaches normal operating temperature, im thinking it could be a sensor
fuel/air or a solenoid operating the engine speed, Note that my vehicle is not
fitted with cruise control so that can be ruled out, I have no problems starting the motor from cold,had new glow plugs several months ago.
This has to have something to do with something controlling the backoff
when decellerating, emission control area but where?

[NiftyNev]

Could be TPS related.



http://toyotasurf.asn.au/forum/viewt...&highlight=tps

Nev

[mickey]

sounds like air getting into the system, maybe via a split fuel line? i'm only saying that because i had a peugot van once, and that did exactly the same thing..every now and then it would just go for it!! i started thinking that's how it should be, and when it wasn't going into "warp drive" it was running unusually sluggish, ha ha..first diesel i'd owned..

anyway, came the day she'd only start, run for a couple of seconds, then die..AA got it sussed straight away, stuck a rubber tube on, and bingo..it was sluggish ever since..just a long shot, but worth a check come daylight..

[it's Jim]

I've got a 2.4 too and mine did this when on the motorway the other week, it kept jumping up and down by about 500rpms, its done it a few over times too.
1) warmed up well on a motorway
2) after leaving ticking over in park for about 15 mins
3) when i was driving for ages at low speed with no turbo on.

Touch wood it hasn't done it for about 2 weeks now, so fingers crossed. Not sure what it is. The only thing i could think off was the turbo pressure release valve. Not sure if thats what you call it but its what i know it as. i put some oil on mine.

[ganghooks]

Thats it Nev Thanks

[QUOTE=NiftyNev]Could be TPS related.



http://toyotasurf.asn.au/forum/viewt...&highlight=tps

Nev[/QUOTE

ganghooks:

Yes right on the nail I found that the Throttle Position Sensor (TPS)
error signal was intermittent causing erratic squirts of fuel, so with some
careful drilling into the side of this sensor i drilled a hole and sprayed some
contact cleaner into it, let it drain out and fitted a small screw into the hole
id drilled 2.5mm refitted in the same position as id marked it with correction
fluid before pulling it off.
Now its fixed my problem, for now, it looks as though it was a dirty wiper
on the error signal carbon track that goes back to the engine management
contol unit,
Ill have to see how much a new one costs
By the way the link you sent, i tried to register and it returned a message saying I have been Banned, Now thats incredible as i never new the site existed until you sent me the link what can we do about that Nev?

[NiftyNev]

By the way the link you sent, i tried to register and it returned a message saying I have been Banned, Now thats incredible as i never new the site existed until you sent me the link what can we do about that Nev?

Send me a PM with all the details you used to register and I'll check it out. If I can't sort it out I'll ask one of the other Admins.

Nev