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Rolling Idle And Back Firing Threw Intake..blah Blah Blah..

  • Thread starter Thread starter foxbodymike87
  • Start date Start date Apr 27, 2013

foxbodymike87

Active Member
Jul 12, 2011
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Apr 27, 2013
#1
  • Apr 27, 2013
  • #1
Ok, first off i know about the checklist and all that but i cant follow diagrams and lists if my life depended on it. so i bought a notch that has a 306, holley heads, cam, trick flow intake, intake spacer, egr spacer, CAI, 30# injectors, smog delete and its an 87 with mass air conversion. the problem is that is has a hard time starting and while its starting it backfires threw the intake alot. and when it starts it won't idle until its warmed up. then whens its warmed up the idle surges. ive cleaned mass air and checked voltage on tps for now. my next step was vac lines but there's hardly any lol. everything looks capped off..the egr spacer has caps on both sides, egr itself has no line on it, lines on the intake haves bolts shoved in them and im more or less overwhelmed and don't know where to start.
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 27, 2013
#2
  • Apr 27, 2013
  • #2
sorry, move to tech
 

jrichker

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#3
  • Apr 28, 2013
  • #3
foxbodymike87 said:
Ok, first off i know about the checklist and all that but i cant follow diagrams and lists if my life depended on it. so i bought a notch that has a 306, holley heads, cam, trick flow intake, intake spacer, egr spacer, CAI, 30# injectors, smog delete and its an 87 with mass air conversion. the problem is that is has a hard time starting and while its starting it backfires threw the intake alot. and when it starts it won't idle until its warmed up. then whens its warmed up the idle surges. ive cleaned mass air and checked voltage on tps for now. my next step was vac lines but there's hardly any lol. everything looks capped off..the egr spacer has caps on both sides, egr itself has no line on it, lines on the intake haves bolts shoved in them and im more or less overwhelmed and don't know where to start.
Click to expand...
Like they say in the Marine Corps... "Can't is Won't"
How bad do you want to fix the problem?

I didn't create the "Surging Idle Checklist” for mechanical geniuses, just the average guy how can read at a 12th grade level and follow directions. You have your marching orders, so get with it.

In case you lost the link, here it is...
See the "Surging Idle Checklist” for help with all your idle/stall problems. You can guess at the problem and throw parts at it, or you can use the checklist to help you find the problem quickly and inexpensively. The checklist is right here in the Stangnet 5.0 Tech forum and you don’t have navigate to some other unknown web site. It‘s free and doesn’t cost anything: at last count there were more than 103,000 visits and still climbing

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 

Dan93fox

Active Member
Nov 29, 1999
175
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39
Bucks County, PA
Apr 28, 2013
#4
  • Apr 28, 2013
  • #4
I had a similar problem, just not as bad as yours sounds. I was pretty sure I had a vacuum leak but not many vacuum lines to check. It turns out I had a vacuum leak around the intake gasket. For what it's worth...
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 29, 2013
#5
  • Apr 29, 2013
  • #5
That good and all but i got a bigger problem..car will crank for like 2 mins while backfiring like a wikd banshee. Then with some thottle effort it will start and stop backfiring..
 

foxbodymike87

Active Member
Jul 12, 2011
739
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39
Apr 29, 2013
#6
  • Apr 29, 2013
  • #6
That good and all but i got a bigger problem..car will crank for like 2 mins while backfiring like a wikd banshee. Then with some thottle effort it will start and stop backfiring..
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 29, 2013
#7
  • Apr 29, 2013
  • #7
Also..it will not stay running...let it idle and it dies
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 29, 2013
#8
  • Apr 29, 2013
  • #8
Does anyone see anything missing??

​
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​
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foxbodymike87

Active Member
Jul 12, 2011
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Apr 29, 2013
#9
  • Apr 29, 2013
  • #9
found a chunk missing from the gasket, but idk if its close enough to be a leak? And that port with nothing on it had a piece of hose on it that i knocked off just by gently poking it.
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
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Apr 29, 2013
#10
  • Apr 29, 2013
  • #10
Did it run fine before? Did you change anything? This just started out of the blue? The gasket missing could definitely be the cause or that piece could have ripped when you removed the intake. Try and put a new gasket on it, that's a cheap, easy fix. Also I cant tell what the is in the second to last pic but if that's the upper intake there should be no open holes on it. If if didn't go anywhere then cap it. And use plugs with a clamp, dont use those hoses with a bolt stuck in it.
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 29, 2013
#11
  • Apr 29, 2013
  • #11
mob said:
Did it run fine before? Did you change anything? This just started out of the blue? The gasket missing could definitely be the cause or that piece could have ripped when you removed the intake. Try and put a new gasket on it, that's a cheap, easy fix. Also I cant tell what the is in the second to last pic but if that's the upper intake there should be no open holes on it. If if didn't go anywhere then cap it. And use plugs with a clamp, dont use those hoses with a bolt stuck in it.
Click to expand...
that second to last pic is the port with no plug on it in the last pic. it was plugged but not securely. so im hoping that is what is causing the car to backfire.
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
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Apr 29, 2013
#12
  • Apr 29, 2013
  • #12
Honestly chances are it was doing the job, but if you have it apart I'd put it back together the right way, I'd unscrew that nipple and thread a plug in it. Again did the car always run like this since you got it? Or has it just started? If its always been like this, tracking down someones hack job can be a serious pain, and you shouldnt be intimidated by the surging check list because its gonna be your only hope. Couple things I would check is spray the motor with carb cleaner while its running to check for change in idle, check the timing, and check the wires on the MAF conversion. The VERY VERY first thing you should do though is check the codes.

foxbodymike87 said:
that second to last pic is the port with no plug on it in the last pic. it was plugged but not securely. so im hoping that is what is causing the car to backfire.
Click to expand...
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 30, 2013
#13
  • Apr 30, 2013
  • #13
mob said:
Honestly chances are it was doing the job, but if you have it apart I'd put it back together the right way, I'd unscrew that nipple and thread a plug in it. Again did the car always run like this since you got it? Or has it just started? If its always been like this, tracking down someones hack job can be a serious pain, and you shouldnt be intimidated by the surging check list because its gonna be your only hope. Couple things I would check is spray the motor with carb cleaner while its running to check for change in idle, check the timing, and check the wires on the MAF conversion. The VERY VERY first thing you should do though is check the codes.
Click to expand...
ive checked timing many times, tps voltage is good, sprayed the MAF, cleaned the IAC, sprayed it down with carb cleaner. its been doing this since ive gotten it, but it seems to be getting worse.
 

foxbodymike87

Active Member
Jul 12, 2011
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Apr 30, 2013
#14
  • Apr 30, 2013
  • #14
Im not quite understanding how to dump KOEO codes? What do i probe and what am i looking for?
 

mob

the guy who hits on his mom
20+ Year Stangneter
Oct 3, 2003
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Apr 30, 2013
#15
  • Apr 30, 2013
  • #15
It's the first topic in the checklist..... There are two connectors behind the driver side fender well, one is one wire with a plug at the end of it, and the other is the bigger weird looking one. U connect the small single wire connector to a wire on the bigger connector, turn the key, and you should hear some clicking and the engine light will start flashing. Which wire you connect it to is specified on the diagram posted by Joe. It's really not that difficult at all but if you find yourself having trouble with it find a friend who can look at it and try and explain in to you. Sometimes our eyes can make things more complicated than they really are.
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
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Kearney, NE
May 4, 2013
#16
  • May 4, 2013
  • #16
If things are written at the 12th grade level, especially if it is a set of lengthy instructions, many people of perfectly average intelligence may have trouble comprehending and completing the steps. There is a good reason most news papers are written at the 5th to 6th grade level. Many people simply comprehend at a lower reading level. When it comes to what we are working on, it also takes a good amount of specialized background knowledge. Remember, we went to the moon on simpler technology.

So, do not give up or be discouraged on first reading. Keep reading it and trying to make sense of the instructions. Chances are you will be able to get it with extra effort and time. But If you do not or can not get it, how about trading someone who is good at this type of thing for something you are good at? Current educational circles call using multiple intelligences, and the rest of us call it bartering. Also, reading it out loud might use a different part of your brain and if might click.
 

foxbodymike87

Active Member
Jul 12, 2011
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May 4, 2013
#17
  • May 4, 2013
  • #17
Yeah thanks, i replaces the ECT and it seemed to have worked for now
 

foxbodymike87

Active Member
Jul 12, 2011
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39
May 5, 2013
#18
  • May 5, 2013
  • #18
ok, new problem. car will not start on a cold start. im not saying cold out i mean its 65 degrees out and it wont start. it will backfire threw the intake once or twice then start up and die..then as the engine gets warmer it will start and stop backfiring but wont idle until operating temps. you can rev it all day long and it wont backfire. only does when cranking? what could that be? i put in a new ECT and that stopped the surging idle.
 

jrichker

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#19
  • May 5, 2013
  • #19
Go back and dump the codes again, and be sure to get the engine running codes.
 
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