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420A Brian crower cams p0300

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@ShonDope Still having issues?
I haven’t been doing too much with it. I did take my valve cover off and checked my timing one mire time. All the marks line up perfectly and even the dowel holes on the cams are both lined straight up so I know it’s not timing. I know it isn’t fuel because I’m running rich. Idk how to verify if it’s spark other than to use a spark tester but I know I have spark because my car runs and the misfire is random through all of my cylinders. As far as the camshaft sensor I’m gonna replace the one I have just because I cracked the plastic by one of the bolt holes... but does the sensor pickup that bolts to the exhaust cam only fit on one way? It looks like it can rotate but when I try to flip it it doesn’t seem to want to fit into place?
 
Yes it only goes on one way, like this.
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I’m not talking about the sensor. I’m talking about the pickup on the inside of the sensor that is attached to the camshaft
 
I’m not talking about the sensor. I’m talking about the pickup on the inside of the sensor that is attached to the camshaft
I was thinking you could try switching the new one out with the old one. Maybe the new one isn't working too well, and you know the old one worked. It should just be held on by one little star head bolt.
 
I was thinking you could try switching the new one out with the old one. Maybe the new one isn't working too well, and you know the old one worked. It should just be held on by one little star head bolt.
The pickup I have in there is the old one. I don’t know where to go to find a new pickup for the camshaft position sensor
 
The pickup I have in there is the old one. I don’t know where to go to find a new pickup for the camshaft position sensor
So the new cams did not come with one? Well, I guess that doesn't matter since it worked before anyway. So have you replaced your CAS?
 
So the new cams did not come with one? Well, I guess that doesn't matter since it worked before anyway. So have you replaced your CAS?
I’ve replaced the cam position sensor and the crank position sensor
 
Okay so I tinkered with the car a little today. When I went out to my car I opened the hood and found my intake cam was sagging a half a tooth inward and there was no tension on top of the cams. I think I might just be a half a tooth off on both cams. It’s either that or the tensioner I just bought is bad and lost tension. Once I get some money to rent a harmonic balancer puller I’ll check it out and adjust it
 
Okay so I tinkered with the car a little today. When I went out to my car I opened the hood and found my intake cam was sagging a half a tooth inward and there was no tension on top of the cams. I think I might just be a half a tooth off on both cams. It’s either that or the tensioner I just bought is bad and lost tension. Once I get some money to rent a harmonic balancer puller I’ll check it out and adjust it
Good to hear that you are making progress. Please update this thread with the results and resolution. Feel free to ask any other questions you have about the car as well.
 
Good to hear that you are making progress. Please update this thread with the results and resolution. Feel free to ask any other questions you have about the car as well.
Actually I do have a question. If I rotate the crankshaft counter clockwise instead of clockwise would that cause the loss in tension in my camshafts?
 
It's normal for some slack to get between the intake and exhaust gear when the motor is off. Rotation the motor backwards won't change the tension on the belt.

When you check your timing marks you will need to rotate it clockwise.
 
It's normal for some slack to get between the intake and exhaust gear when the motor is off. Rotation the motor backwards won't change the tension on the belt.

When you check your timing marks you will need to rotate it clockwise.
My timing was all tight the other day when I went out to check it but I rotated the crankshaft about 3 teeth to the left to check the marks on the cams. And then the next day there was hella slack in the space between the cams and my intake came was turned slightly clockwise
 
Ok so I looked into the timing again... I matched it up to all the examples I could find online and on this forum and my timing is good. I checked every way I could think of and even used a screwdriver in the cylinder to see if the piston was in the right spot when my cams lined up just in case my crankshaft mark was off. So I’m going to finally rule out timing. But... I pulled the spark plugs and my cylinder 1 plug looked dirtier than it should for only being about 300 miles old. And I found my IAT sensor connector bent. So I took pictures of the sensor and my cylinder 1 and 4 spark plugs. Plus I got a picture of my freeze frame data for you guys. If you guys can tell me anything from these pictures it would be really helpful
 

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Ok so I looked into the timing again... I matched it up to all the examples I could find online and on this forum and my timing is good. I checked every way I could think of and even used a screwdriver in the cylinder to see if the piston was in the right spot when my cams lined up just in case my crankshaft mark was off. So I’m going to finally rule out timing. But... I pulled the spark plugs and my cylinder 1 plug looked dirtier than it should for only being about 300 miles old. And I found my IAT sensor connector bent. So I took pictures of the sensor and my cylinder 1 and 4 spark plugs. Plus I got a picture of my freeze frame data for you guys. If you guys can tell me anything from these pictures it would be really helpful
You can buy a new IAT for less than $10. So I would do that for sure. That helps the ecu determine AFR's, and could also pull a fat vacuum leak.

As far as the plugs go, they look pretty clean. If it was running too rich they have have thick black carbon build up. If it was running too lean they would be copper-brownish and burnt. What brand are the plugs? A quality set of plugs goes a long way compared the Chinese shit.

What kind of scanner are you using?
 
You can buy a new IAT for less than $10. So I would do that for sure. That helps the ecu determine AFR's, and could also pull a fat vacuum leak.

As far as the plugs go, they look pretty clean. If it was running too rich they have have thick black carbon build up. If it was running too lean they would be copper-brownish and burnt. What brand are the plugs? A quality set of plugs goes a long way compared the Chinese sh**.

What kind of scanner are you using?
The plugs are ngk coppers gapped at .045. The scan tool is a Cen-Tech scan tool
 
Have you tried swapping the plug wires and injector wires around to see if it throws a specific cylinder code?
Ya I’ve tried both. It always comes up with a random misfire in all 4 cylinders. Do you think a performance ignition coil and wires would make a difference or not?
 
Ya I’ve tried both. It always comes up with a random misfire in all 4 cylinders. Do you think a performance ignition coil and wires would make a difference or not?
I have no doubt it would make a difference, but I will not guarantee that it will fix your problem. If you've got the money and time go for it. At this point I'm not sure how you haven't found the problem.
 
I have no doubt it would make a difference, but I will not guarantee that it will fix your problem. If you've got the money and time go for it. At this point I'm not sure how you haven't found the problem.
So this is my live data after replacing that sensor and installing an msd coil
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Everything looks like it's supposed to except for the spark advancement. I'm not sure why it fluctuates so much.
Ya that’s what is so frustrating. Everything seems to be working fine except for the spark advancement. My car runs fine and everything but the spark advancement is weird and I keep getting the p0300. I’m gonna buy another IAC to see if it helps with my stalling at stops but I don’t know what to do about my spark
 
The stock ECU uses ignition advance and the IAC to control the idle speed. Ignition timing can react much quicker then the IAC, so timing is used to correct small fluctuations in the idle.
 
The stock ECU uses ignition advance and the IAC to control the idle speed. Ignition timing can react much quicker then the IAC, so timing is used to correct small fluctuations in the idle.
So other than getting a megasqirt or something what else can I do?
 
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