'93 NA with 1.8L, 200km to a tank.

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quasyt

'93 NA with 1.8L, 200km to a tank.

Postby quasyt » Tue Aug 05, 2014 4:46 am

Basically, picked up an NA which has had a 1.8L conversion.
Noticed very poor fuel mileage, ~200-240km to a tank. (Filled to the click and run until empty). Also builds soot up on the rear bumper.
Car has original 1.6L AFM, not sure if that makes a difference.
Thinking it may be a faulty O2 sensor though(?)

Any input from the gurus would be brilliant.

Thanks.

emily_mx5
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Re: '93 NA with 1.8L, 200km to a tank.

Postby emily_mx5 » Tue Aug 05, 2014 8:50 am

Change:
Spark plugs (because $15 why not)
Run a bottle of Nulon fuel system cleaner
Change fuel filter
Ecu thermo sensor (most likely the problem, telling it it's like -40degrees so it's running really rich
Check for exhaust leaks (can mess with O2 sensors readings)
Change O2 sensor (they don't really do too much on NA6 though)
Check air filter (could be old and blocked)
Swap in known working AFM (I had one fail and car ran not very well)

There is heaps more but that's the major things.



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speed
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Re: '93 NA with 1.8L, 200km to a tank.

Postby speed » Tue Aug 05, 2014 9:48 am

x2 what Emily said.
Na6 AFM on a 1.8 doesn't sound right.


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emily_mx5
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Re: '93 NA with 1.8L, 200km to a tank.

Postby emily_mx5 » Tue Aug 05, 2014 11:12 am

If it's had a 1.8 swapped into an na6 car, you have to retain the stock na6 engine management stuff like afm.


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speed
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Re: '93 NA with 1.8L, 200km to a tank.

Postby speed » Tue Aug 05, 2014 12:23 pm

emily_mx5 wrote:If it's had a 1.8 swapped into an na6 car, you have to retain the stock na6 engine management stuff like afm.


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Really, well there you go.
I thought that you'd have to change ecu and all. Thanks


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Jeo
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Re: '93 NA with 1.8L, 200km to a tank.

Postby Jeo » Tue Aug 05, 2014 2:33 pm

When I first got my 1.8l swapped NA6 it to was running pig rich all the time.

My solution was to put in an after market ECU and ditch the AFM.

quasyt

Re: '93 NA with 1.8L, 200km to a tank.

Postby quasyt » Tue Aug 05, 2014 8:40 pm

Emily, you are a machine!

Ill go trough the list and smash them out quicksmart.
Though, I need more info on the ECU thermo sensor.

khlmx5
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Re: '93 NA with 1.8L, 200km to a tank.

Postby khlmx5 » Sun Aug 10, 2014 8:42 am

Let us know how u go please.

Mr Morlock
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Re: '93 NA with 1.8L, 200km to a tank.

Postby Mr Morlock » Sun Aug 10, 2014 6:46 pm

if you change the plugs before fixing the problem then all it will do is is deposit soot on them and the same for other things. Clearly the car is running far too rich.


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