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Discussion Starter #1
just recently bought a 93 2l 155 skinny with the 8 valve engine and have been having problems with kangarooing at low revs which i see has been discussed at length on this forum.

checked the lambda probe and afm as advised and have discovered that the air temp sensor in the afm appears to be faulty. no change in resistance across terminals 4 and 5 of s5 irrespective of engine temp, measured voltage drop with engine running across batt -ve and pin 5 of s5 and it appears to be stick at 4v approx. (this should drop as the engine warms up i think?)

i have already cleaned out the afm and air temp sensor so looks like its knackered.

can the air temp sensor be replaced on its own or am i looking at a new afm?

any advice would be much appreciated.
 

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[.....]the air temp sensor in the afm appears to be faulty. no change in resistance across terminals 4 and 5 of s5 irrespective of engine temp, measured voltage drop with engine running across batt -ve and pin 5 of s5 and it appears to be stick at 4v approx. (this should drop as the engine warms up i think?)
The air temp wont change as the engine heats up, only the water temp. The air temp is the incoming air so you'll have to wait for the weather to change to measure the ohms :lol: ;)

AFAIK on the 8v there isno knock sensor (or is that the V6?).... anyway , apart from knock measurement, the air temp is only used to fine tune the air intake measurement - colder air =more dense, hotter air=less dense.
However I dont think a wrong air temp would cause such severe symptoms that you describe.

How does it idle? Have you checked for vac leaks?
Also I think the AFM is the adjustable mechanical flap type..... try a search
 

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symptoms arent that severe, just some light kangarooing at around 1300-1500 revs if yer light on the throttle. only happens when driving in traffic. ticks over fine and runs grand when ye stick the foot down so i suspect it is just a "fine tuning" issue. cant find any leaks and lambda seems to check out ok. afm is the mechanical flap type.
i thought as the engine warmed up the wee thermistor/sensor thingy in afm had warmer air drawn over it, raising the temperature and thus reducing the voltage output from the sensor that is fed to the ecu.
checked my engine temp sensor in the manner and found that as the car warmed up the voltage at the sensor output dropped from around 4v at start up to around 1v when the engine is up to temperature.
was expecting to see the same thing happen on the air temp sensor as well.
thought warm air went through yer air box and afm when engine was up to temp??:confused:
 
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