14 degree BTDC timing adjustment - NA (MKI)

To do this mod, you need a timing light with inductive pickup and a 12mm ring spanner. An external tachometer is nice. Warm the engine to normal operating temperature, stop it, then connect the timing light and the tachometer (there is a blue plastic +12V connector under the bonnet to power the light, and an IG- contact in the DIAGNOSIS connector for the tach - they can both be earthed to the engine block in any convenient place).

Start the engine and bridge the TEN and GND contacts in the DIAGNOSIS connector with a paper clip (a map of the contacts is in the Solutions… board of this forum). The engine revs may drop - you need them to be at 850rpm so adjust the idle speed if necessary with the throttle body air adjustment screw. Don’t bother setting the idle speed before bridging the contacts as it is normally under the control of the engine management system - you have to turn this feature off first.

Now use the timing light to see where the yellow-painted notch on the crankshaft pulley lines up with the numbers on the scale above it. There are usually two notches (the other is white) and they will typically line up with 10 and “T”. You want the one lining up with “10” to be lined up two notches further left, which is 14 degrees BTDC. To do this, find the crank angle sensor, on the back of the exhaust side of the cam cover on a 1.8, loosen its long-headed retaining bolt a turn or so and rotate it very, very gently by hand until you get the desired setting. This may affect engine speed, so reset the base idle to 850rpm and re-check. Then stop the engine, disconnect your paper clip, timing light and tach and drive!

Some gotchas:

1) 1995 cars only have one timing mark, line this up with the 14 degree mark on the timing belt cover.

2) The timing marks on the pulley are often difficult to find because of rust and dirt. If yours is like this, remove spark plug no.1 and put the car’s dipstick in the hole. Turn the crankshaft pulley clockwise using the car’s wheel nut spanner, watching the dipstick until you reckon the piston has reached top dead centre. This should give you a much better chance of finding those little notches.

3) Disturbing the crank angle sensor may cause a small oil leak from a perished O-ring. It’s a risk you take.

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