The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support Fuel Injector Clinic
Please Support ExtremePSI

420A Brian crower cams p0300

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ShonDope

Proven Member
50
14
Apr 16, 2017
Marysville, California
Has anyone had any issues with a p0300 code after installing the Brian crower stage 2 cams? I’ve replaced everything but the ECM and it just won’t go away. I also have an issue with my car stalling when I go to a stop. It’s not all the time, but it’s almost like it chokes but I’ve replaced the IAC. I’ve reset my timing and replaced the components 3 times already so I know it’s not a timing problem. Please help me! 99 eclipse rs
 
Usually when doing cam work you will need a tuning solution. Since you replaced both cams with stage 2's I wouldn't expect the car to run perfectly until you tune it.

I have only an exhaust cam and my engine has its little problems since I haven't tuned it.

You say you haven't replaced the ecu, do you have Megasquirt? Or have you played with the OBDII at all?


Oh, and how's your timing? Do you have adjustable cam gears? Stock ones?
 
Usually when doing cam work you will need a tuning solution. Since you replaced both cams with stage 2's I wouldn't expect the car to run perfectly until you tune it.

I have only an exhaust cam and my engine has its little problems since I haven't tuned it.

You say you haven't replaced the ecu, do you have Megasquirt? Or have you played with the OBDII at all?


Oh, and how's your timing? Do you have adjustable cam gears? Stock ones?
I have stock cam gears and a stock ecu. I was hoping I wouldn’t have to buy a mega squirt just for the cams. How do I play with the OBDII?
 
I have stock cam gears and a stock ecu. I was hoping I wouldn’t have to buy a mega squirt just for the cams. How do I play with the OBDII?
Dyno tuning.

Due to the nature of the stock ecu and stock parts, you can't do much tuning with it. You might be able to make the car run ok, but I would plan for a Megasquirt in the future. Especially if you want to do any more internal mods.
 
Dyno tuning.

Due to the nature of the stock ecu and stock parts, you can't do much tuning with it. You might be able to make the car run ok, but I would plan for a Megasquirt in the future. Especially if you want to do any more internal mods.
I thought you couldn’t tune the stock ecu at all?
 
You can't reflash the stock ECU, but you can tweak the fueling some with a piggyback system. Something like a SAFC. It just tricks the ECU into adding or subtracting fuel. You would have to look at fuel trims to see what the ECU is trying to do with your fueling to know if you need to make changes.

But honestly, I don't think that's your problem. Cams alone shouldn't cause stalling problems. Some do experience misfire codes with large cams but the stalling seems strange to me.
 
You can't reflash the stock ECU, but you can tweak the fueling some with a piggyback system. Something like a SAFC. It just tricks the ECU into adding or subtracting fuel. You would have to look at fuel trims to see what the ECU is trying to do with your fueling to know if you need to make changes.

But honestly, I don't think that's your problem. Cams alone shouldn't cause stalling problems. Some do experience misfire codes with large cams but the stalling seems strange to me.
I know my ecu is trying to cut fuel. It’s been running at around -20 for my long term fuel trim at idle and my spark advance switches between advancing and retarding. It doesn’t retard much but every 15 seconds or so it’ll go about -1.8g
 
Have you read through the causes and symptoms list of this code? That'd be the first place to start.

This is the reason why everyone who plans to actually buid their 420a needs Megasquirt.

Here is some info. Courtesy of dsmtalk.com
You must be logged in to view this image or video.
 
Have you read through the causes and symptoms list of this code? That'd be the first place to start.

This is the reason why everyone who plans to actually buid their 420a needs Megasquirt.

Here is some info. Courtesy of dsmtalk.com
You must be logged in to view this image or video.
I’ve replaced everything on the list except for my ecu
 
Somebody else's input would be nice on what I think: Maybe these cams are not working well with your camshaft position sensor?
I just don’t understand why though. These are the most popular cams for these cars and I’ve even replaced the camshaft sensor. Although I did notice oil in between the sensor and the pickup. Is that normal?
 
I just don’t understand why though. These are the most popular cams for these cars and I’ve even replaced the camshaft sensor. Although I did notice oil in between the sensor and the pickup. Is that normal?
There's oil in mine too. And I'm not throwing a code.

I guarantee you the problem here is very simple. You just have to narrow down the options to find exactly what it is. If you feel like you've done everything, do it again. You are missing something here.

Just curious, have you ever done a compression test on this engine before?
 
There's oil in mine too. And I'm not throwing a code.

I guarantee you the problem here is very simple. You just have to narrow down the options to find exactly what it is. If you feel like you've done everything, do it again. You are missing something here.

Just curious, have you ever done a compression test on this engine before?
No I haven’t done a compression test yet
 
You said you've replaced everything? So that includes:
- plugs
- plug wires
- coil pack
- 02 sensors
- fuel injectors
- camshaft position sensor

Is this correct?
Ya I’ve also replaced the fuel filter, fuel pressure regulator and the crankshaft sensor
 
Sounds like you are just replacing a bunch of parts instead of actually diagnosing the problem. This happens too often, everyone seems to do it. This pretty much never works, and puts people out more money than they have to spend.

Try resetting the code. Pull both the battery cables and let it sit for 10 minutes this way everything can reset. Drive it, and see if it comes back on.

The three causes of misfire are:
- no fuel in cylinder
- fuel not igniting
- improper timing

For an engine to run correctly you need:
- fuel
- spark
- compression


Once you have verified everything here then you should have found your problem. If not, report back with some news.

- Solomon
 
Sounds like you are just replacing a bunch of parts instead of actually diagnosing the problem. This happens too often, everyone seems to do it. This pretty much never works, and puts people out more money than they have to spend.

Try resetting the code. Pull both the battery cables and let it sit for 10 minutes this way everything can reset. Drive it, and see if it comes back on.

The three causes of misfire are:
- no fuel in cylinder
- fuel not igniting
- improper timing

For an engine to run correctly you need:
- fuel
- spark
- compression


Once you have verified everything here then you should have found your problem. If not, report back with some news.

- Solomon
Most of the parts were old and worn out anyway so I replaced them. I’ve reset the code and pulled the battery cable already. I even replaced the battery terminals to make sure there was a strong connection. I can post some pictures tomorrow of my live data
 
Sounds like you are just replacing a bunch of parts instead of actually diagnosing the problem. This happens too often, everyone seems to do it. This pretty much never works, and puts people out more money than they have to spend.

Try resetting the code. Pull both the battery cables and let it sit for 10 minutes this way everything can reset. Drive it, and see if it comes back on.

The three causes of misfire are:
- no fuel in cylinder
- fuel not igniting
- improper timing

For an engine to run correctly you need:
- fuel
- spark
- compression


Once you have verified everything here then you should have found your problem. If not, report back with some news.

- Solomon
Also I just tested the resistance of my brand new coil pack. It’s at 4.4 ohms for the primary coils. Isn’t it supposed to be less than 1 ohm?
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top