Another Protege5 thread

engine is knocking, i have no idea what caused it, but it was probably to running lean under boost. i was pushing it hard on the highway and it was doing fine until i tried to start it again. it barely turns over and knocks at idle once it starts
 
i’m thinking i’m gonna put some nicer internals in but i have negative money right now so im going to see how bad the damage is. maybe ill just have to replace bearings or rods. if im replacing rods im going to get nicer ones and im going to look into pistons as well. it will be properly tuned next time around, but if you want to run low boost the consensus for the auto ecu is it will work but just make sure to watch afrs and have gauges to monitor everything
 
can anyone give me any ideas?
i’m sure that it’s rod knocking but it only happens at idle/startup, i have oil pressure and it looks to be normal, it was running lean in boost and it definitely had a boost spike right before i got off the highway.

i knew i was pushing it. i think it has to be bent rods, there’s no way it spun a bearing because the oil pressure is unaffected. it sounds like it’s coming from the intake manifold side of the block but it’s so loud ive ruled out anything stupid like a ac line rattling.

i think under the conditions i had it in it could only be a bent rod or two. if it is im going to buy some k1 rods and forged pistons, i don’t want to open this thing up again. im planning on getting a manual transmission from the junkyard and a couple other parts and doing a swap but im not doing that until the auto goes.

the auto held up well to whatever i threw at it, but i know transmissions don’t just blow, they slowly slip and then fail. i was running 8-9 psi with a terrible tune and im lucky the engine lasted how long it did. the automatic transmission made me feel a little safer knowing it couldn’t hold the same power as the engine even though it still wasn’t the weak point.

tuning it was the hardest thing to figure out and i think im going to go with a speeduino, they’re cheap and im going to just run the Protege5 ecu to control the transmission, and some other stuff. the speeduino would control all injectors and spark plugs, and it’ll run off my wideband o2. they’re incredibly cheap and if you have time on your hands, it’s the most versatile tuning option out there.

i’m hoping i can get the car running soon, im cracking it open tonight and taking a look. i just hope i wont need machine work. i’m going to see how the pistons held up, i deleted the oil squirters and plugged them with socket head caps (thanks jackie chan!!) the stupid part of that idea was that i didn’t have forged pistons. there was nothing to cool them down, no oil, no fuel.

i’m lucky there isn’t a hole in my block. i was telling my friend, hindsight is 20/20 and i just get to do it better this time. we already rebuilt his engine twice, his timing skipped a week and a half ago and bent his valves and we had it running in a week. i’m hoping it’s a similar situation for my engine. i’ve learned a lot about there cars in the past couple months and im not too mad to have something to work on.

when it’s running again i need someone to help me find what’s causing my rough idle. i have tried messing with everything and it still gives misfire codes. i welded the egr shut and i tried to remove every vacuum line, but it still reads -10hg at idle and bounces while the rpm does.

also, instead of the spark plug non fouler mod, i just welded another bung in after the second cat, and the computer was happy.

i know there’s a couple people wanting to boost an automatic, so if you have any questions send me a pm, im sure i could answer a good chunk of stuff. sorry i haven’t been posting much, when it’s all tuned and reliable, ill definitely post a lot about everything i did and what i learned.
 
i wish it was easier to pull this motor, the transmission makes it so difficult, it’s just as hard to try and pull the engine separately, than it is to take all of the suspension apart to pull the axles
 
got it out, the bearings are damaged but the rods look fine and the bearings dk t have as much damage as i was expecting. i’m confused and i still feel like i haven’t found the knock. the torque converter bolts were looser than when i put them on. and the crank pulley too. but everything pointed me towards rod knock, and the bearings are definitely damaged but they’re more scored and i think it’s possible that it ran out of oil during break in from an oil leak. oops. i just don’t see anything that would sound like what i heard the other night. maybe i don’t know enough about engines and everything’s way more damaged than i can see with my eyes but if it starts knocking when i start it next time i know it won’t be the engine and the transmission is what i’ll be looking into. if the transmission is done for then im going to just put a manual in.
 
engine is knocking, i have no idea what caused it, but it was probably to running lean under boost. i was pushing it hard on the highway and it was doing fine until i tried to start it again. it barely turns over and knocks at idle once it starts
Damn it, man that sucks. Were the rings gapped for boost? It could be piston slap. The fsde also has an issue where oil can pool on one side of the pan when turning and starve the motor. If you take apart the oil pump it can give you a lot of info on what happened.
 
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