Scottster Posted August 9, 2007 Report Share Posted August 9, 2007 The car has been developing a miss over the past few months, and it is starting to get to the point where I should do something about it. It basically has a rough idle in gear, hesitates off the line sometimes, and you can hear it through the exhaust standing behind the car. What are some diagnostic tests I could do to find out the source of the problem? I thought about just getting new wires, but I figured it would be wiser to see what you guys say first. Thanks Quote Link to comment Share on other sites More sharing options...
Supreme Cutlass Posted August 9, 2007 Report Share Posted August 9, 2007 The car has been developing a miss over the past few months, and it is starting to get to the point where I should do something about it. It basically has a rough idle in gear, hesitates off the line sometimes, and you can hear it through the exhaust standing behind the car. What are some diagnostic tests I could do to find out the source of the problem? I thought about just getting new wires, but I figured it would be wiser to see what you guys say first. Thanks How old are the spark plugs? I would go plugs>wires>ignition system(coils, etc.) Quote Link to comment Share on other sites More sharing options...
Scottster Posted August 9, 2007 Author Report Share Posted August 9, 2007 The plugs are basicaly new. They were replaced in November when I got the car. So wires then? That's what I was thinking, but is there anyway to test them or something to know for sure? Quote Link to comment Share on other sites More sharing options...
Supreme Cutlass Posted August 9, 2007 Report Share Posted August 9, 2007 Physical damage on wires is a big flag that they're bad (burns, cuts, or in my case simply falling apart) Quote Link to comment Share on other sites More sharing options...
needsomehelp Posted August 9, 2007 Report Share Posted August 9, 2007 What kind of plugs are they? Quote Link to comment Share on other sites More sharing options...
pwmin Posted August 9, 2007 Report Share Posted August 9, 2007 i would look at the wires for any physical damage and look at the plugs to see if there is any tracking on them. that is a sure sign it needs wires. you can also run it in a very dark place and spray soapy water on the wires and see if they are arcing anywhere. or, if youre feeling adventurous, run the car and pull plugs off one at a time w/ something good and insulated and see if theyre getting good spark. but dont come to me if you fuck up, lol, and dont ground yourself on the car. if it has bosch or autolite plugs, i would replace them w/ some AC Delcos even if they appear to be good. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted August 9, 2007 Report Share Posted August 9, 2007 It could be a fuel problem also. How old is the fuel filter? How much fuel pressure are you getting at the fuel rail? Can you smell strong exhaust when standing behind the car at idle? How old are the injectors? Mine acted similarly to yours and after replacing my injectors it runs near perfect. Quote Link to comment Share on other sites More sharing options...
Scottster Posted August 10, 2007 Author Report Share Posted August 10, 2007 It could be a fuel problem also. How old is the fuel filter? How much fuel pressure are you getting at the fuel rail? Can you smell strong exhaust when standing behind the car at idle? How old are the injectors? Mine acted similarly to yours and after replacing my injectors it runs near perfect. I'm not sure about the age of the fuel system compnents. The exhaust doens't have an strange or particular smell to it, it just sounds funny. How much did new injectors run you? I'll don't know what brand of plugs were used, but I'll find out tommorow. Quote Link to comment Share on other sites More sharing options...
pwmin Posted August 10, 2007 Report Share Posted August 10, 2007 its always a good idea to change the fuel filter esp when you dont know when it was changed. it cheap insurance and easy to replace. i would run some BG44K through the fuel, too. new injectors 25# injectors: http://www.zzperformance.com/grand_prix/products1.php?id=297&catid=113 you wont be able to use them w/o a chip cuz theyll be too big, but theyre not too expensive Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted August 10, 2007 Report Share Posted August 10, 2007 It could be a fuel problem also. How old is the fuel filter? How much fuel pressure are you getting at the fuel rail? Can you smell strong exhaust when standing behind the car at idle? How old are the injectors? Mine acted similarly to yours and after replacing my injectors it runs near perfect. I'm not sure about the age of the fuel system compnents. The exhaust doens't have an strange or particular smell to it, it just sounds funny. How much did new injectors run you? I'll don't know what brand of plugs were used, but I'll find out tommorow. I used some Ford C302 yellowtops. They are 22lb/hr and work great in my TGP. They cost me $249 for all 6. I'm not sure if they'd work on a n/a 3.1 though. Quote Link to comment Share on other sites More sharing options...
PCGUY112887 Posted August 31, 2007 Report Share Posted August 31, 2007 Check ebay for injectors, I got 6 brand new OEM DOHC injectors for a lil over $100... Quote Link to comment Share on other sites More sharing options...
gp90se Posted August 31, 2007 Report Share Posted August 31, 2007 willing to bet its the ICM or a coil going bad. To test the wires, get a spray bottle, wait till it gets dark, start the car and mist the wires, watch for arcing. I had a coil get nasty, when i hit it with water the damn thing esploded. autozone can test the coils and icm for free if you yank them out Quote Link to comment Share on other sites More sharing options...
pwmin Posted August 31, 2007 Report Share Posted August 31, 2007 willing to bet its the ICM or a coil going bad. To test the wires, get a spray bottle, wait till it gets dark, start the car and mist the wires, watch for arcing. I had a coil get nasty, when i hit it with water the damn thing esploded. autozone can test the coils and icm for free if you yank them out what do they actually test them for? Quote Link to comment Share on other sites More sharing options...
joey b Posted September 3, 2007 Report Share Posted September 3, 2007 willing to bet its the ICM or a coil going bad. To test the wires, get a spray bottle, wait till it gets dark, start the car and mist the wires, watch for arcing. I had a coil get nasty, when i hit it with water the damn thing esploded. autozone can test the coils and icm for free if you yank them out If you take your ICM out I highly suggest you drive right by AZ and stop at NAPA. On more than 1 occasion I've had AZ tell me the ICM was bad but the Napa test proved faulty. The problem was that the tester at AZ doesn't get it hot enough. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.