need help with pinging

[sideshow]

hi too all
now that its summer here is australia my 1uz hilux is starting to ping on hot days where outside is about over 30 degrees celsius

what i do know is when im statinary for afew minutes stopped at a set of lights the engine must get abit of heat soak and as i drive on light throttle after that it pings its head of very badly sometimes

its a very strange problem becuase i cannot pin point a cure for it

there are a few things i think

1 fuel pressure is ok checked with gauge but metal lines from the efi intank pump are 6mm then just ater they exit the tank goto 8mm from efi fuel filter then 8mm to engine
i dont htink this is a prob but just wondering if with 6mm pipes maybe causing a fuel flow problem

2 Radiator not big enough thermo fan switch on and off ok so engine doesnt overheat i think but maybe the radiator which is std hilux one maybe does not flow enough water therfore the back of the engine gets hot

3 the hot air under bonnet is not expelled properly which i have put spacers under the back of bonnet didnt fix problem fully

it is annoyinh this problem because i dont know exactly what to do
if i could just replace or upgrade a part then its easy all i got to do is pay money

i run an octain booster in the fuel on hot days but the right side back of engine pings badly so im sure its heat soak or bad water flow at back of engine

just wondering if anyone has had these issues before

maybe its abit lean at light throttle

maybe i should try a 72 degree thermostat or maybe even try fitting a better radiator which flows more water

if anyone could suggest anyhting it would be great

thanks

 

[highlander]

That is odd.. mine wont ping on 38C days... normal here in Puerto Rico.

 

[highlander]

One other thing.. how are you detecting this pinging? audible??


there is a TSB for these engines for the front main bearing. The bearing will cause a "pinging" sound not related to pinging. They stated that the front bearing was .010 to thin i think.. got to look that up.

 

[sideshow]

im pretty sure its pinging

when the engine sits at a set of lights it gets worse just as i take off

but ill get a friend to listen to it too

its very easy to hear it

sounds like the back of the engine

 

[Lextreme II]

Is the pinging occur only during hot days? How about at idle? Valve noise is very common in the 1UZ engine.

 

[sideshow]

yes only on hot days say over 30 degrees
or if the engine has been idling for over 5 or 10 minutes
when i take off on light throttle it pings badly but once i start drivin say down the highway and get cold air into the engine bay it doesnt ping as bad

so im sure its pinging

its not really related to coolant temp cause temp gauge reads ok and thermo fans turn on and off

i think its more related to engine bay temps
i think its gettin heat soak
i have wired up many of these 1uzs and never come across this prob

 

[200sx-v8]

Could it be that your ignition is to much advanced?

 

[mycarhasposessedme]

Dont think the 6mm pipe would be a prob as the fuel rail inlet and crossover pipes are all 6mm.
I take it its been happening with more than one tank of fuel.
Do you run premium with the booster or regular unleaded?
What brand of fuel do you use?
Do you always buy from the same garage? they might have a bad batch.
A hot day will always show up a batch of crap fuel.
I have read posts on other forums here in Oz regarding differences in fuel octane tests of some of the major brands and there are sometimes large fluctuations even between batches especially the premium varietys. They tend to drop there octane level very quickly with age (talking weeks) so always buy from someone with a good turnover of premium. Appologies if i'm telling you stuff you already now.
Cheers
Trev

 

[sideshow]

its hard to know if its bad fuel cause if the day is nice and cool it wont ping

i always run premium unleaded
and if its hot i chuck abit of octain booster

its just weird that it does it on a hot day when ive been staionary but the temp gauge reads ok
maybe i should try another more accurate temp gauge

 

[Lextreme II]

Perhaps bad injector/s?

 

[sideshow]

i got injectors serviced and i ran a decarbonising thingy thru the manifold

injectors were fine and wasnt much carbon in top end so even after 12 yrs the engine

seems ok

 

[Lambo]

Pinging and fuel expained

Sideshow ,Found this article maybe it will help has good info.
http://www.mrturbo.co.za/FUELS, DETONATION, PREIGNITION, OCTANE ETC.htm
Regards
Lambo

 

[quadcam boat]

run a line from your fuel rail into the cab for a fuel pressure guage and make sure your fuel pressure isn't dropping off. That will rule out your pump, lines, regulator ect.- everything on the fuel supply side of things except the injectors.

 

[sideshow]

yer ive run a fuel press gauge all is ok

the only thing is flow i cant check

but its only at 10% throttle so i doubt its lack of fuel

i think its more a case of fuel rail heatin up

i put some octain booster in with the fuel and it does make it better

so im startin to think maybe the ecu is advancing the timing too much

and its ok when cold but when hot its bad

i might get a multimeter with a temp gauge and measure fuel rail and back of block temp

 

[sideshow]

i just found out abit more news

i went and did some wiring on a 1uz crown and he had afew spares so i got the obdII diagnostic plug

so today i wired up the obdii plug into my crown wiring as much as i could

i then connected my snap on diagnostic scanner into it and i finally could read live data

the only prob is it doesnt have crown but it does have soarer and lexus

so i sort of used lexus but no matter which one its same results

when driving say at 100 kph

at about 4 to 7 % throttle the timing is a 40 to 45 degrees and sometimes hits 50 so i recon on a hot day this could cause probs

not sure if this is normal but would be good if i could data log it

but my next step is to heat wrap the fuel lines goin up to the engine

it does seem to be a heat affecting fuel problem

anyway its just interesting to see what live data im getting from it

pity i cant read what the gbox is doin too

 

[Zuffen]

Jim,

Would you like to borrow my Crown ECU and see if it makes any diference?

We could do a tempory swap (so I can remain mobile) and if I inherit your problem we can be sure it's your ECU.

 

[gloverman]

Hello

Have you checked the basic's. How many K's have the spark plugs done or could the cambelt be a little loose. I have seen many cars, especially toyotas that do weird things when the belt is a little stretched. The ignition timing figures seem very high. Don't these engines have factory knock sensors. Whats the scanner reading from these? Good luck.

 

[sideshow]

ok thanks

im goin to get a 3.5 diff for it in a week then ill put heat wrap round the fuel lines
and see

then i can meet you and i could try yr ecu

im back to full time work tomorrow so its hard to get time off to fix my car

 

[KDog]

I assume you knock sensors are wired up correctly to the ECU?
Sorry I can't remember which ECU you are using, is it the older Crown uz131 or the later ones?

You should not be getting any knocking if the knock sensors are working correctly. I would be checking these. You should be getting error codes 52 and 55 if your knock sensors aren't working. If you get a 53 thren your knock circuit in the ECU has problems.

 

[sideshow]

the ecu light doesnt come on and i get no errors
just strange y does it run 40 to 50 degrees advance at 4% throttle
i will try another ecu

unless my snap on scanner is inaccurate

i will try to put my scanner onto another 1uz and see what live data i get