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hi all ive got an 89 mpfi touring wagon and am worried bout the pinging that has started. the motor is a new import motor done 100,000kms that is fitted atm. i have checked and adjusted the timing and lowered it to 18 btc and now running premium unleaded (95octane in Tas) the car still pings, mainly coasting light throttle if u give it a squirt no pinging. please help as im worried bout the motor any info appreciated

cheers BEN

Is the knock sensor connected & working ?

look crazy question but ive looked it up twice and looked 3 times on the car The knock sensor is on the drivers side below the throttle cable on top of the block next to a breather hose and its a threaded hole? isn it? cause im going mad i cant find it nor the connector pleasae help me....

ive found the coolant thermosesor on the manifold and the purge control solenoid valve i know the knock sensor is on the block. plz help

cheers

I think I read somewhere on this board that the mpfi don't have the knock sensor, it was only on the turbos, but I'll stand corrected on that one. Strange that it is pinging on light throttle and ok when you put your boot into it, as it's normally the other way around?

hi think ur rite mate the turbo motor mite b the only motor with a knock sensor. ha no wonder i couldn find it...lol (im a dick)

yeah i thought that bout pinging too mainly when u boot it, well its def pinging though just want it fixed mite have to checked for fault codes? ive checked all of the connections i could find all ok dont know what else?

anyway cheers BEN

i've had to run my mpfi on optimax or equivilant to stop the pinging.another thing the suba experts told me was that it may take a couple of tanks to sort out something to do with the computer resetting.

subelover wrote:hi all ive got an 89 mpfi touring wagon and am worried bout the pinging that has started. the motor is a new import motor done 100,000kms that is fitted atm. i have checked and adjusted the timing and lowered it to 18 btc and now running premium unleaded (95octane in Tas) the car still pings, mainly coasting light throttle if u give it a squirt no pinging. please help as im worried bout the motor any info appreciated

cheers BEN

your timing is showing its to advanced for the fuel compression mixture.
you can eliminated the compression as this would not have changed....either
1/ you fuel is very bad, in that case drain and fill with known good fuel...note..hi occtane fuel is a waste in these engines as the bang factor is higher but the length of the burn is shorter..so 92 is the best buy for your buck on ea,s as the burn is longer than high grade fuels..but the bang is not as hot/but the compression ratio would have to be in the 10,s to get any benefit from 95 and higher...as these have lower compression ratio,s..its a waste.... like feeding scotch fillet to a cat...
2/you computer will respond to ignition changes imediatly..providing you have connected the green connectors..and have the throttle switch on the pedal closed...this is the only way to garantee accurate programming of the ecu on the l serie,s...

3/ 1 thing to consider is that your centrifugal advance on the dizzy is not sticky or locked up..as this may give you a higher than desired base timing and will have made your 18 degree setting redundant...so this is a good thing to check,before setting the timing..make sure the rotor has a spring loaded effect and returns completely clockwise...

Depending on what dizzy is in there will depend if it has a centrifugal advance as the late ones where fixed.

But as above i would retard the ignition more to around 12degrees

have checked and adjusted the timing and lowered it to 18 btc and now running premium unleaded (95octane in Tas) the car still pings

Is it normal to have the timing so far advanced on an NA motor, 18 btc is more like EA82T timing, I dont have my book here to check but I would have thought it should be more like 8 btc?

The later model mpfi had a hot wire system there idle was 20 degs the earlier flapper systems had there idle at 8 degs.
My 85 mpfi runs at 6 to 8 deg and still pings when you floor it so ive had to run 95 ron..
If you go to http://www.finleyweb.net then you can download the service manual for the mpfi.

and double check that the dizzy is indeed one for an efi motor...if its off a carby motor you set the static advance at the usual 8-10deg, the advance is fully controlled only by the springs.

Yes, its weird ay how the efi one has setting at 20-22deg, but that is because
the ecu controls the timing by retarding it off the advance created by the springs.

If timing is right, pinging can also be caused by incorrect sensor f/b from Eg engine temp,AFM, etc...leading to incorrect fuelmap........

cheers guys thanks for the replys and great info...

checked the spring of the rotor in the dizzy a little bit stiff lubed it and freed it up a bit all good it springs back ok now and i then reset the timing to 15 degrees btdc going to try that for a few days and c if that helps

cheers BEN

Is your motor a 85-86/3 plug ecu/flapper afm or the 87-94/4 plug ecu/hotwire afm

The 85-86 had a mech disty with cenrifigal and vaccum advance. which was set at around 8deg. The 87-94 had an optical disty that was set at 20deg and then ecu's map retarted the timing as needed (turbo models had a knock sensor that retarted the timing when pinging was detected)