Mx-3 running very poorly, cant track down issue

Ok, im going to try to be as explainatory as possible here. If you dont want the qhole story skip to the last paragraph.

About a year ago i blew my head gasket and warped my head, engine was running fine, water hose had blew out and i lost all coolant while on the highway in traffic and didnt notice before it was too late, the head was bad so i used blue devil for a bit until my standard transmission had a pinion problem.

i found another tranny on the cheap, decided to replace the cracked head in the meantime while i replaced the tranny, kept the same injectors, lifters, and camshaft, swapped everything else in the head (note, first time ive done anything this big and yes i made sure the torque was correct on the head and everything was installed properly) and in the process i broke a few sensors (engine temp and coolant temp, both physically broken, plugs and ends) i replaced engine temp and it immediatly fried next time i started it and i repaired the plug to the coolant sensor (which is now malfunctioning), the engine was running very poorly upon putting it all togethor and i cross checked everything (rings, valves, gaskets etc…), then in the process of testing my injectors started to fail and i tried to replace them all (if one is failing they may all be on the brink)

the ones i ended up buying were OK but seemed a bit off (bought them off ebay but i still made sure they were tested and tested them myself, came out positive and fine) but the plastic tip on 2 of them were very loose, after putting the injectors on the car the car ran worse than ever, higher idle, extremely rough acceleration, and if i pressed the gas anywhere other than a little bit or floored it would sound like it was pumping air or something along the lines(hard to explain, but not firing well at all)

so i put the old ones on except the stuck one and it ran pretty well again compared to with the new injectors, still slightly had the problem, upon taking the injectors out 2 tips got stuck inside and fell into the engine, i thought since they were plastic the engine would burn it and i believe it did, engine ran same after burning it.

at this point its running ok as long as i dont press the gas in the middle, then anther injector went out, still unable to afford new ones i put a new one running poorly in and the car ran the same, suddenly, the 2 cylinders that had the old injectors started to get slight oil in the cylinder and would slightly foul the plug, so i have 2 poorly firing cylinders now and the only 2 cylinders pulling the injector plug off of adds a reasonable difference to engine performance are the 2 with new injectors. i inspect the car further and test it as much as i can at different places and different mechanics, almost every obd2 reader gives me different codes, one for fuel pressure regulator (which i checked and is leaking a bit of fuel) and vacuum hoses, which i checked and were all ok, next reader scanned bad amf and engine temp sensor (which fried upon plugging in) and another place read that my car was an mx-6 and bad o2 sensors, a mechanic told me my fuel pressure regulator was causing all this which i find hard to believe, after further personal checking my timing was off by 1 tooth this whole time, not sure if this can cause this many issues but it is like that.

Then my distributor burned out and i had to replace it (specifically the module), car ran a bit better on new module but still. whole time im having a minor oil leak that turned into a bad one, on brand new gaskets everywhere, the oil started smelling extremely strong of gas, no smoke whatsoever in exhaust (but a very very slight blue if i put a flashlight to it, which is normal, i have no catalytic converter) and oil leaking around timing cover but not onto belt, my alternator also burnt out before leak was too bad (wasnt getting oil on it) and had to replace that. throughout this time my new tranny started giving me problems too, i had a new hole come out of nowhere by the driver side output shaft, and both output shafts were bad and leaking, i put pegatanque(a cement type glue for fuel tanks and tranny leaks and whatnot) on the hole (hasnt leaked since) and replaced the seals, and i started to notice it was also leaking from the main input shaft seal on the inside (great).

Having no time to replace that seal and drop the tranny cuz all the other issues im having with the car while maintaining 15 credits in university and 40hr a week work i put bluedevil in the tranny, now my clutch is slipping (i replaced the clutch brand new with the tranny) and i believe its from the gear oil as well. the leak is slowly stopping now, and the rest of the parts i know are bad for sure, thanks to the 2 weeks off for corona virus, i will be fixing(those including injectors, amf sensor (ive been getting problems with it since before error codes), plugs, coolant/engine temp sensors, timing(forgot to mention i changed tensioners on it), valve cover gasket (where most of the oil is leaking from but not leaking into the cylinder from) and anything else i might suspect bad) but i want to know what you guys might think as well could be wrong, 2 cylinders are barely firing, its hard to start, and acceleration is terrible and only runs with gas barely being touched at all and being floored, otherwise sounds like a lawnmower, but sounds fine barely touched or floored. im at a complete loss and no mechanic is willing to help me, what the hell should i do…

nobody wants this cursed car and i cant afford to get a new one whatsoever because of how much ive already invested in this car. (also forgot to mention i have a fairly bad exhaust leak) i believe the problem is stacked minor problems but the oil leak into the cylinders is boggling me without more smoke or reasons it could be bad rings and brand new valves/valve seals… also this all happened mostly in the span of 2 months, the beginning happened about 4 months ago when i finally was capable of starting repair on the car, any ideas?

I’ll check back later. Maybe the Cliff’s notes will be available then.


Please don’t. Keep it as short as possible. By the time I got half way through reading I already forgot what you said in the beginning. Also, it helps inserting paragraph breaks for easier reading.


I can’t speak for anyone else, but I refuse to even attempt to read a “wall of text” that lacks paragraph breaks.


I read the entire narrative. In my opinion, the car needs a new engine, clutch, and transmission. It should go to the scrapyard.


I could not stay with that mess either . But I did see something about being a student and 15 credits . I hope the person does not turn in papers written like that.


Sorry, long night, didnt realize i had so much to say about all of it, fixed it as best as i can, last paragraph is how car is running as of now.

I honestly wish i had the option to scrap it but there arent even scrapyards here, in fact i would have to pay to get rid of this car so not much of an option and economy here is trash as hell.
Im in the process of fixing quite a few things i k ow for a fact are wrong, will be posting updates to how the car is running, if i fix all problems great, otherwise, third persons opinion on what might be wrong is appreciated, btw at this point almost everything in the engine is brand new and tranny only had 25k miles on it.

Take off the license plates and vin plate,leave the key in the ignition and the doors unlocked, and park it on the street somewhere not close to where you live.


not a bad idea

Day one of repair:

Took off crankcase following mass oil leaks, found out oil was leaking from crankcase/crankshaft seals (both sides) and thats why my clutch was slipping, trying my best to get the seals tomorrow but all stores will be closed due to COVID-19 so im shit out of luck, not even sure if my parts coming in the mail will make it, im going to also, since im already at the crankcase, go ahead and change the rings and bearings, i dont feel its necessary to change the rods or pistons though, any thoughts?

Also update:

upon further inspections tranny is no longer leaking from most places, had some gear oil still lingering around but upon cleaning wasn’t constantly leaking, oil was from crankcase and it was mixing with gear oil making it impossible to tell which of the two were actually leaking, leaks should be contained soon, will update again after tomorrow.

Unless a piston has a hole in it, I’d leave them be. Id have a good look at the rod bearings and journals though. Also, if you don’t have one you’ll need a ridge reamer to get the pistons out and a ring compressor to get them back in.

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Ill take them out and check them tomorrow, ill see if the mechanic down the road can lend tools or a hand while this whole mess is happening (his business should be closed so he might not mind lending me a hand)

Unless he rebuids engines as part of his portfolio, he’s not likely to have those tools on hand. You can get them if you need at


There are multiple copies of the VIN that are etched in various places on modern vehicles:

I know the places and a grinder will get’em off, not that i will but if all goes wrong this is probably the solution

What year and mileage is this MX3 and where do you live that there are no scrapyards?

And unless the car was involved in a crime,no LEO is going to bother looking for them.

219k miles but the engine has ± 105 miles, it was replaced before i bought it, and tranny has 130k miles