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420A Brian crower cams p0300

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This is how my car runs at idle. When I’m revving or driving it sounds and feels normal. But at idle it looks kinda broken up
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Those compression numbers are normal. I would't worry about those.

And I agree with @Cherry that is the sound of cams.
What the video doesn’t show is the engine randomly bouncing every few seconds. I figure it’s due to the misfires. But otherwise it sounds like it’s running fine. Anyway, I just got my new TPS and I noticed it came with an O-ring and a paper gasket. My old sensor was missing the paper gasket. So maybe that’s what the problem is... I’ll have to wait till the morning to see though because my battery is dead and I’ll have to jump the car. If this doesn’t work I’m gonna start testing the wiring for the cam and crank sensors for any kind of loss of signal
 
What the video doesn’t show is the engine randomly bouncing every few seconds. I figure it’s due to the misfires. But otherwise it sounds like it’s running fine. Anyway, I just got my new TPS and I noticed it came with an O-ring and a paper gasket. My old sensor was missing the paper gasket. So maybe that’s what the problem is... I’ll have to wait till the morning to see though because my battery is dead and I’ll have to jump the car. If this doesn’t work I’m gonna start testing the wiring for the cam and crank sensors for any kind of loss of signal
Is your battery toast? A dying battery can cause more problems than you realize. Changing my battery was like a whole new world for the car.
 
Is your battery toast? A dying battery can cause more problems than you realize. Changing my battery was like a whole new world for the car.
No the battery is only about 3 months old. I didn’t close my door all the way so my light stayed on the whole night. But after installing my new TPS I started the car and it idled hella rough and surged like crazy. After I disconnected and reconnected the wires it mellowed out but I would stay on for a minute then stall. So I’m pretty sure the new sensor I got is bad. I’ve had the worst luck with this car
 
No the battery is only about 3 months old. I didn’t close my door all the way so my light stayed on the whole night. But after installing my new TPS I started the car and it idled hella rough and surged like crazy. After I disconnected and reconnected the wires it mellowed out but I would stay on for a minute then stall. So I’m pretty sure the new sensor I got is bad. I’ve had the worst luck with this car
That is weird. What brand sensor is that?
 
That is weird. What brand sensor is that?
Standard ignition. My problem might be that I’m buying all my sensors online. I’m gonna swap out the gaskets in the new sensor with my old sensor and put my old sensor back in and check it. But I think I’ll probably get a new cam sensor from O’Reillys or something and see if I might’ve bought a bad cam sensor too
 
I'm running out of ideas here. I'd say check to see if your cat is clogged. A clogged cat will over-stress the engine at lower rpm's and sometimes kill it. You can drop the downpipe and look inside the cat with a light. Hell, you should probably check both ends just to be sure.
 
I'm running out of ideas here. I'd say check to see if your cat is clogged. A clogged cat will over-stress the engine at lower rpm's and sometimes kill it. You can drop the downpipe and look inside the cat with a light. Hell, you should probably check both ends just to be sure.
I checked the cat a few months ago just before I put the cams in. I was running a test pipe and put the cat back on when I changed my muffler
 
Well then it shouldn't make a difference if your coming to a stop or moving unless the problem is with the IAC. You say you replaced the IAC but I literally replaced every sensor except this one and the problem remained.


Does it idle a little high if you put the clutch in while going down hill?
 
I wasn’t able to mess with it much due to the holidays. But I ended up buying another tps sensor and another cam sensor just in case one of them was a dud and I just replaced my battery again today because it went bad from all the sitting it’s done. I’m getting the same problems. But I’m convinced it’s something electrical because the problem is too inconsistent to be mechanical. If the timing was off or something was wrong with the cams it would be a consistent issue. I’m gonna replace my spark plug wires again just because some ngk wires online and when I got them I saw glue at both ends of all of them which has bugged me since I got them. I’m wondering if they might not be legit or something. If the spark plug wires don’t work I’ll probably just have to save up and have a shop look at it
 
So I found something online about people that get the P0300 code after a cam swap and people that have stalling issues after a cam swap. It seem that with the aftermarket cams they can sometimes freak the computer into thinking something is wrong so they kick the misfire codes and depending on the cams you buy it can mess with the stall speed when slowing down. So it says to have the engine code disabled in the computer and to change the stall speed based on whatever specs the cams are. I just don’t know if you can do that with the stock computer. It seems like a simple task and wouldn’t require a full tune but dsm’s just have to be difficult. I did find a forum post last night that someone said the 98-99 420a can be reprogrammed with a Chrysler machine though. I’m hoping it can be that simple instead of paying $500 for a new computer just to gain like 20hp
 
I did find a forum post last night that someone said the 98-99 420a can be reprogrammed with a Chrysler machine though
Good luck finding one of those. I've heard the backstory about that, and the info about it is supposed to be private. And there are only a couple of them known in existence. See what you can do, but and aftermarket tune is the best way to go.
 
Are your injectors firing properly? Still think this is just a simple tuning solution. You threw in a stage 2 cam into an other wise stock car. I've thrown that code more times than I can remember on alot of builds I've done. Tuning always cleared that code. You can always put the stock cams back in and see what that does. All this time you already wasted on everything else might as well see how it reacts with the stock cams back in.
 
All this time you already wasted on everything else might as well see how it reacts with the stock cams back in.
That would be a bigger waste of time. He already stated that the car ran fine and did not have this code before the cams. The name of this thread is asking why the new cams caused him to throw a code.

And yes, he also stated that the injectors are all firing.
 
That would be a bigger waste of time. He already stated that the car ran fine and did not have this code before the cams. The name of this thread is asking why the new cams caused him to throw a code.

And yes, he also stated that the injectors are all firing.

Welp nothing else clearly worked LOL. So you can keep picking at straws or see how it reacts when its back to stock. And If the car ran fine before the cams then that's prolly a big clue as to what the issue is. See how it runs on stock cams. If it solved your issue then great and dont run em till you can properly tune it. You've ruled out everything else what do you have to lose at this point. It's not gona cost you anything like these sensors and every other part you already changed.
 
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Welp nothing else clearly worked LOL. So you can keep picking at straws or see how it reacts when its back to stock. And If the car ran fine before the cams then that's prolly a big clue as to what the issue is. See how it runs on stock cams. If it solved your issue then great and dont run em till you can properly tune it. You've ruled out everything else what do you have to lose at this point. It's not gona cost you anything like these sensors and every other part you already changed.
The issue isn’t whether I could tune it or not. The issue is not knowing what the issue necessarily was. If something was bad then it wouldn’t make sense to try to tune it. But now I’m just trying to see if I can get a simple fix by getting into my ecu and making my engine code inactive or if I absolutely have to by an aftermarket ecu. So I’m gonna get some adjustable cam gears and try to get a simple tune done if possible before putting all that money into an ecu when I’m not building my car for any crazy gains or anything
 
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