If it is an injection engine it could be the temperature sender, if it has gone short circuit then the computer will think that the engine is warm and will not richen the mixture. Fuel will be present but not enough if the engine is cold. A quick check is to unplug the temperature sender and then try to start. With the sender unplugged the computer gets a signal that the engine is very cold.
The temperature sender is probably on the water manifold/elbow that is fixed to the left side of the cylinder head. Normally they are white or blue with a two pin connector. I confess to not being completely familiar with the 5 cyclinder engine.
Will not scrap it no matter how much it costs.... love this car even if its a headache to work on, hey balboa where is the air flow control thing you are talking about (sorry i know nothing about engines, just computers...)
A compression test will tell you if the timing has hopped, but you can do it this way too:
Valve/Cam Timing check: Some of this has been a while, I’ve recently worked on a 5cyl engine ( 93 NG), where the cam mark is different, so some of this is from years ago:
Disconnect battery, remove TB top cover.
Bottom end: Rotate the engine via the bottom pulley, with a ( I think it’s a 27mm) socket until its at TDC, top dead centre.
You should see the notch on the lower TB cover and on the bottom pulley , they should align, Confirm that you’re at tdc by checking through the small window on the gearbox and looking for the 0 mark on the flywheel, that it aligns with the pointer in the window.
If you can’t make out the marks you can do this, but be careful not to jam or drop anything down the cylinder. Get a long thick cable tie, or stiff insulated electrical wire (something not too hard, non metallic ,slightly flexible), and remove the spark plug from cyl no1. Feed the tie though the plug hole into the engine. Rotate the engine slowly while bobbing the tie up and down so it doesn’t get stuck on the upstroke, and you will feel the piston moving, and stop when it’s at it’s uppermost point, ie TDC, Now go look again for the marks and they will be easier to spot, highlight the bottom pulley marks ( the one on the pulley, and the one on the lower cover) with white paint, so you can spot them quicker next time.
Top end: Some 5 cyl engines have different cam timing sprocket positions, but most should be correct when the dimple (little dot) on the back of cam sprocket in in line with the flat metal strip on the RHS of the valve cover ( the long strip that’s under the 10mm valve cover bolts)
Others have an arrow on the front of the sprocket, and it should be around 11 oclock position.. when at TDC
If these marks are not to seen, rotate the engine by hand 1 more rev until your highlighted TDC marks align again, the marks could be 180degrees away, if you don’t have oil splash cover inside the valve cover, you can remove the oil filler cap, you will see that both cam lobes on cyl no.1 will be pointing up ward, ie valves closed.
Find the HT plug lead for cyl no.1 on the distributor, unclip the dizzy cap, and check that the rotor arm is pointing to cyl. No1.
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