94' 1.6 DOHC Engine Issues ...

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SilverSurfer60
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94' 1.6 DOHC Engine Issues ...

Post by SilverSurfer60 »

Bought a 94' MX-3 (with 93K) for my daughter from and it died 4 days after purchase. I had the guy get the timing belt changed and water pump changed the day prior and it was idling high (1500rpm) when I picked it up. Note: I talked to the mechanic who supposedly changed the belt and pump and he seems to have no clue what's wrong. Well, it turns over but won't start. The compression in the cylinders follows: 100, 25, 50, and 25 (wet 175, 100, 100, etc.). No smoke of any kind ... it's getting gas, relay and fuses are good, and it has spark ... is there an anomally with these motors or am I missing the obvious (head, rings, etc?). Thanks for any ideas or help ...
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ariesdude
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Re: 94' 1.6 DOHC Engine Issues ...

Post by ariesdude »

SilverSurfer60 wrote:The compression in the cylinders follows: 100, 25, 50, and 25 (wet 175, 100, 100, etc.)
The normal compression is 185 psi -

either something went terribly wrong with the timing belt install or you need a new engine.
94 Mx-3 Precidia
1.8L 4Cyl DOHC newGen BP (used to be B6DE) ATX
http://www.mx-3.com/phpbb2/viewtopic.php?t=54032
http://www.cardomain.com/id/ariesdude
SilverSurfer60
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Post by SilverSurfer60 »

Cool. Do you what engines can be interchanged on this frame? Thanks.
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neutral
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Post by neutral »

It's possible to swap in an early 90's 1.8 BP DOHC engine from a protege or escort gt but even that swap requires resolving wiring harness and ECU issues I believe. If reading your post correctly, the car died AFTER the timing belt was replaced and was running fine before that repair? If so, can almost guarantee that the mech slipped a couple of cam gear teeth out of position when installing the new belt. Easy to do on a DOHC motor but no excuse for a shop to mess that up. And with the cam gear(s) out of position, definitely would mess with your compression results too 'cause either the exhaust valves or intake valves are out of position and not sealed/seated when they need to be during the piston stroke.

fwiw, same thing happened to me on my daughter's 2.0 DOHC 626 - the one and only time I had a shop do this repair. Car ran fine when I brought it in and the timing belt was done as preventive maintenance before she took the car on a 17,000 mile x-country road trip. I pick it up repaired as the shop was closing with it idling high (and a little choppy) at the curb. Turned out it was idling high (normal) cuz the engine was cold (middle of winter) and once warmed up and the idle adjusted itself to normal warm operation, it just died unless ya kept pressing the gas pedal to keep the idle up and clearly had very little power on accel. Unlike your MX-3, the 626 2.0 is an interference engine w/possible permanent valve damage from incorrectly positioned cam gears. I freaked on the shop and they had the car towed back to them. Sure nuf, the mech had slipped a couple teeth outta position on one of the cam gears when putting on the new belt.
Last edited by neutral on March 8th, 2007, 1:25 pm, edited 1 time in total.
Image -Jim
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ariesdude
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Post by ariesdude »

Since your engine is a 94 DOHC - you have two (relatively) easy options
1) Get a 90-94 protege engine (1.8 - BP) - you would also need the entire wiring harness and ECU. There will be some issues with the dash wiring and also the speedo sensor - but there are soultions posted somewhere in the forum.
2) Get a 95-98 protege engine (1.8 BP newer version) - this engine is "almost" plug and play. You can either get a complete harness and ECU or make it work with your existing 1.6 harness and ecu. I have done this swap - follow the link in my signature.

Another option is to swap a 2.0 litre DOHC ZETEC engine from a Ford escort zx2 - i am contemplating this swap and as far as i know the engine would bolt on without any modifications - but wiring could be a problem.
94 Mx-3 Precidia
1.8L 4Cyl DOHC newGen BP (used to be B6DE) ATX
http://www.mx-3.com/phpbb2/viewtopic.php?t=54032
http://www.cardomain.com/id/ariesdude
SilverSurfer60
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Post by SilverSurfer60 »

Aries,
Thanks for the quick response and assist. I'll hit the boards and do some more research on the options. Peace
SilverSurfer60
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Post by SilverSurfer60 »

Neutral,
So is worth having them rebuild the current engine or go for a replacement? I'm not at all familiar with these guys but bought it for my daughter to get back and forth to college. Any advice I can give the new shop guy who's stumped as well? Thanks for your insight and help. SS60
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neutral
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Post by neutral »

Hey there SS60. With two grown daughters myself, I know exactly what you're going through. Aries info was informative but I'm guessing you don't really have the time or inclination to pull that engine in your "spare time" in the driveway and do a customized motor swap for a car that YOU'RE not even gonna drive. :wink:

If you brought the car into the shop running fine, the shop owes you the car running just as fine as when you brought it in. Either way, if it'd help ya out, give me a call and we can talk through stuff. Check your msgs. (Link at top of this page) I just PM'd my contact info.
Image -Jim
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