Welcome to Camaro Z28!

Welcome to CamaroZ28.Com, the ultimate Source for Camaro enthusiasts! Here you can join over 90,000 Camaro enthusiasts from around the world discussing all things related to Camaros and more. You are currently viewing as a guest which gives you limited access to view discussions

To gain full access to our forums you must register for a free account. As a registered member you will be able to:
  • Participate in over 40 different forums and search/browse from over 5 million posts.
  • Upload your Camaro details to your Garage
  • Post photos, respond to polls and access other special features
  • Gain access to our free marketplace to buy, sell and trade Camaros, parts and more.
All this and much more is available to you absolutely free when you register for an account, so join our community today today!

If you have any problems with the registration process or your account login, please contact support.


Go Back   CamaroZ28.Com Message Board > 1967-2002 Powertrain Discussion > LT1 Based Engine Tech
Sign in using an external account
Register Forgot Password?
Register Garage Photos Blogs FAQ Members List Social Groups Links Calendar Search Today's Posts Mark Forums Read Z28LiveVendor Directory


Reply Post New Thread
 
 
LinkBack Thread Tools Search this Thread Display Modes
Old 09-05-2005, 01:11 AM   #1
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
The Phantom PO300 code!

I've had this damn PO300 "mutliple engine missfire" for the last 2 or 3 months. I've replaced the opti, and the opti harness. New plugs, and new wires. I can't figure out for the damn of me where it is comming from! I currently have the hotcam in my car, i know it does create a slight miss, but I got the car re-tuned twice. So according to SpeedInc it shouldn't be there and yes I've brought it back to them numorouse times.I'm just gettin tired of waitin weeks at a time gettin my car back. Emissions testing is comming up. So does anybody have any quick fixes or suggestions? I am at a totall loss. I know one of my buddies said there is a certain code I can put into the computer via Tec 2 to clear it out permanently, but the only problem with that is, I don't know if its somthing seriouse or not. Thanks gentlemen.

-GTP Stage 2 Heads
-Hot Cam setup 1.6
-Full exhaust
-Long Tubes
-Cutout
-O2 trip sensors
-MSD 6al
-Everybolton
-Walbro 255
-Race tronix 32lbs
- Holley AFPR

Just a list of stuff that may have an effect on answers. If you need anymore information just post, and i'll reply promptly!
This ad is not displayed to registered members.
Register your free account today and become a member on CamaroZ28.com!
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "

Last edited by BlackBird97; 09-05-2005 at 04:49 AM.
BlackBird97 is offline   Reply With Quote
Old 09-05-2005, 03:25 AM   #2
Registered User
 
Join Date: Mar 2002
Location: Grand Prarie,T.X
Posts: 640
Re: The Phantom PO300 code!

try your wires see if there is a short by the headers being so close. also try the cps i have a new one im the box if you want to buy it dont need it, i had a short in the wires
__________________
97T/A all bolt ons and full suspension. R.I.P
1990 300zx
1lt1 block 424 and the 355 future...
2007 Z06 485Hp 450tq. Filter and tune only
Zeueses 97 RamAir is offline   Reply With Quote
Old 09-05-2005, 04:49 AM   #3
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
Re: The Phantom PO300 code!

CPS? What's that?
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "
BlackBird97 is offline   Reply With Quote
Old 09-05-2005, 07:21 AM   #4
Registered User
 
Join Date: Nov 1998
Location: Louisville, KY
Posts: 2,626
Re: The Phantom PO300 code!

CPS = Crankshaft Position Sensor

The good ol' PO300. It seems to be a different cause for everyone who has had it. Most don't post back what caused theirs. I chased it for a couple of months, before the scan tool finally pinpointed the cylinder the miss was in. It turned out to be a bad plug wire that looked perfectly fine, until I took it off, then I could see the fine black line by the sparkplug boot.

Do you actually have a miss, or is the car just giving the code?
__________________
Artificial intelligence is no match for natural born stupidity.
moparman is offline   Reply With Quote
Old 09-05-2005, 03:58 PM   #5
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
Re: The Phantom PO300 code!

Quote:
Originally Posted by moparman
Do you actually have a miss, or is the car just giving the code?
It says it's missing, I can feel the stutter of the car missing at some points. So I am guessing it's missing. Or hoping it's missing...so then I know it's somthing that can be fixed haha.
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "
BlackBird97 is offline   Reply With Quote
Old 09-05-2005, 06:16 PM   #6
Registered User
 
Join Date: Jan 2002
Location: Goose Creek, SC
Posts: 275
Send a message via Yahoo to CamaroRob97
Re: The Phantom PO300 code!

Like mentioned before have you checked your fuel pressure at all? with the vehicle running hook a gauge up to the fuel rail (with the shradder valve removed) and pun it through a nice wide RPM range. Also you say it feels as though is missing, and your sure the plug wires are good, i know its a PITA but check all the other to make sure non are carboned up, also if they are good we know u got spark, put a noid light on each injector to make sure they're each firing...can't seeing it being you ignition module....cam position sensor??
just my $.02

hope this helps

Rob
__________________
1988 Camaro RS '72 357 *Down for the rebuild/interior update*
2002 Z28-FRA, SLP -lid, STB, fanswitch, Sphon SFC's, DMH cut-out, LS7 cluitch kit, Edelbrock LTs & Y-pipe, Hooker CB, NGK TR55's, Nitto 555's

Last edited by CamaroRob97; 09-05-2005 at 06:19 PM.
CamaroRob97 is offline   Reply With Quote
Old 09-05-2005, 07:03 PM   #7
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
Re: The Phantom PO300 code!

Arrite, I've been doing alot of research on the Crank Position Sensor, I found that its about 70 bucks from GM. I couln't find the Cam Position Sensor, checked Chiltons, engine diagrams and whatnot. Does the 97 LT1 Have one of these ? All I could find was the Crank Position Sensor. Looks like an easy install.
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "
BlackBird97 is offline   Reply With Quote
Old 09-05-2005, 07:28 PM   #8
Registered User
 
Join Date: Jan 2002
Location: Goose Creek, SC
Posts: 275
Send a message via Yahoo to CamaroRob97
Re: The Phantom PO300 code!

Well in all honesty its been bout 2.5 years since i've even really touched an LT1 let alone an f-body, so yeah my Cam posi. sensor info may be off. But as far as the CPS Yes its at the bottom of the timing cover...can't remember if its d/s or p/s...(Man i need to get to the desert so i can my off the 'clipse an get another f-body )
__________________
1988 Camaro RS '72 357 *Down for the rebuild/interior update*
2002 Z28-FRA, SLP -lid, STB, fanswitch, Sphon SFC's, DMH cut-out, LS7 cluitch kit, Edelbrock LTs & Y-pipe, Hooker CB, NGK TR55's, Nitto 555's
CamaroRob97 is offline   Reply With Quote
Old 09-05-2005, 08:09 PM   #9
Registered User
 
Dave89IROC's Avatar
 
Join Date: Aug 2002
Location: Melvindale, MI, US
Posts: 4,680
Re: The Phantom PO300 code!

Quote:
Originally Posted by CamaroRob97
Well in all honesty its been bout 2.5 years since i've even really touched an LT1 let alone an f-body, so yeah my Cam posi. sensor info may be off. But as far as the CPS Yes its at the bottom of the timing cover...can't remember if its d/s or p/s...(Man i need to get to the desert so i can my off the 'clipse an get another f-body )
CPS is on the pass side of the timing cover, at the bottom

LT1 don't have a seperate cam sensor, all it needs one for is fuel/spark synch, so the high and low res pulses for the opti suffice, and all it uses the crank sensor for is misfire detection
__________________
ASE Certified Master Technician
2004 Blazer Xtreme, Indigo Blue
1990 K5 Blazer LT1/700R4/NP241
1989 Camaro IROC-Z **SOLD**
MichiganSpeed
Dave89IROC is offline   Reply With Quote
Old 09-06-2005, 01:26 AM   #10
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
Re: The Phantom PO300 code!

Hmm I see, well tomorrow I'm goin under the car, checkin for burnt wires, and investigating the CPS. Are those things prone to go out after a while? And Rob, it's arrite man, there will be an F-body there for ya when ya want one! We'll all still be here!
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "
BlackBird97 is offline   Reply With Quote
Old 09-06-2005, 01:43 AM   #11
Registered User
 
madwolf's Avatar
 
Join Date: Jul 2001
Location: DeKalb, IL
Posts: 4,580
Re: The Phantom PO300 code!

On OBD2s (particularly LT1), P0300 can show up after installing a cam that is more radical than stock. If it does, there is not much you can do about it since the system was designed for checking misfire on a stock cam. Having said that, I'm almost 100% sure a new sensor won't solve your issue. Your best bet, in my opinion is to have the code disabled. You should be able to pass with 2 "NOT READY" flags and this would only trigger one.

Last edited by madwolf; 09-06-2005 at 01:48 AM.
madwolf is offline   Reply With Quote
Old 09-07-2005, 02:10 AM   #12
Registered User
 
Join Date: Sep 2003
Location: Chicago IL
Posts: 451
Send a message via AIM to BlackBird97
Re: The Phantom PO300 code!

Yeah figured out it isn't the CPS....I am leaning twords the wires. But if it's not that. May god help me!
__________________
-2006 Subaru Legacy 2.5i-
-1997 FireBird Formula WS6 A4 (12.402@111.9 1/4) -All Motor-Heads and Hotcam-*Having Some Technical Difficulties*

"MUST GO FASTERRR!!!!! "
BlackBird97 is offline   Reply With Quote
Old 09-08-2005, 04:47 PM   #13
Registered User
 
madwolf's Avatar
 
Join Date: Jul 2001
Location: DeKalb, IL
Posts: 4,580
Re: The Phantom PO300 code!

If you don't want to continue doing work in vain and replacing things without any results, read my above message.
madwolf is offline   Reply With Quote
Old 09-08-2005, 04:52 PM   #14
Registered User
 
Z95m6's Avatar
 
Join Date: Oct 2001
Location: newton, kansas, USA
Posts: 6,067
Re: The Phantom PO300 code!

Quote:
Originally Posted by madwolf
If you don't want to continue doing work in vain and replacing things without any results, read my above message.
lol.
__________________
(current) 03 Cobra with a Whipple
(sold probably dead by now) 1995 Z28 m6
The Z
Z95m6 is offline   Reply With Quote
Old 09-08-2005, 04:52 PM
 
Reply Post New Thread

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 01:23 PM.


Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
SEO by vBSEO ©2011, Crawlability, Inc.
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.
Copyright © 1996-2013 CamaroZ28.Com. All rights reserved.