bad pinging between 1000-1400rpm , had code 71

[phillipguru]

So i've had a slight slight ping for about 6 months, really faint.

in the past 2 weeks the pinging has gotten louder, but still only at about 10% throttle and in the 1000-1400 rpm range. Then a few days ago it threw the 71 CEI code, which is malfunction egr. I knew i had a small crack in the pipe. So i blocked off the pipe on the back of the intake manifold and blocked it off on the side where the egr valve is. I put the 10k ohm 1/2 resistor on the air temp sensor and sure enough the code is gone but the pinging still is there.

I'm wonder where to go from here. the car isnt overheating, octane booster doesnt do anything. i've changed the plugs(not for this issue but just because i was bored). Its still pinging but throwing no codes , no lights.

I was thinking I could replace the 2 front 02 sensors with universals, and maybe replace the knock sensors. But i have no idea where the knock sensors are on this car.

Any help, thoughts, opinions, guides, howtos anything would be great.

Also I have seen this somewhere, someone had the readings the 02s should read , something like 6.5 ohms or something, can someone clarify that and if its possible to check the knock sensors to be in operational range.

 

[Peewee]

Are you sure its pinging??

If its knocking that badly that its audible, then the knock sensors should go in to overload and throw an 'excessive knock' code (53)

 

[Toysrme]

Sure you have good plugs (that are not too hot) in there?
Clean of carbon?
Remember no EGR makes knocking at low / part throttle worse if it's present.

 

[sideshow]

mine used to ping stupid knock sensors do crap

mine used to ping cause it used to get hot
the std temp gauge read still within limits
when i put an accurate temp gauge it used to get over 100
now with new rad it sits under 88

when u are cruising the timing is around 45 to 55 degrees on std ecu
and if temp gets abit high on my shitbox then it would ping

 

[Peewee]

the std temp gauge read still within limits
when i put an accurate temp gauge it used to get over 100

Your standard temp gauge didn't move because the factory motor was designed to get up to 110degC without worrying.

So the gauge wont move until about 115degC, and by then the 1UZ would have cooked itself.

 

[phillipguru]

fark it, i think i'll just swap in another engine or buy a porsche

 

[turboteener]

You need to hook your EGR system back up. It is costing you power and causing combustion temps to be too high, thus causing pre-igntion. Reset the computer and fix your EGR system.

 

[Loroh]

You need to hook your EGR system back up. It is costing you power and causing combustion temps to be too high, thus causing pre-igntion.

Come agian??

I thought the EGR system would cause this problem, hence the reason he Deleted it!

Mine has no EGR from factory (asuming your talking about the "recycle the exhaust gas back into the intake of the engine system")

 

[turboteener]

The EGR system uses inert exhaust gases to cool the intake charge at part throttle. When it is disconnected the timing map that the factory spent thousands of dollars perfecting for all conditions is no longer accurate. The combustion temperatures that the engine was mapped for are much higher now hence you get part throttle detonation.

The reason he disconnected the EGR system is becuase it was leaking(not working). Fix the EGR system and adjust the engine back to factory specs.