My car's been acting up.

Codeman · March 5th, 2011, 09:13 PM

Ok well my car has been acting up for awhile now.

It cranks over for a long time when it has been sitting over night before starting. It is colder outside too right now in the 20s or so. I have a brand new battery that I put in last year, I cleaned the posts and clamps just incase.

It just seems to me that it cranks and cranks and then like partially starts and then barely fires and will start up. It only happens over night. I was thinking maybe a bad check ball in the fuel pump but that should not matter, I have tried cycling the key twice to prime it and it did the same thing.

Also today I was driving around and it started idling really rough. It felt like a broken motor mount. But when I would give it gas it would run fine. I didn't feel a miss once I put my foot on the gas. And I noticed that when it was idling rought the AF ratio on my wideband would slowly go lean to sometimes 16:1 or more then quickly drop back to rich. I am wondering if I don't have some 02 sensors that are acting up. I just bought a fuel filter it has been at least 2 years since I put one on so I figured I would try that first. It was just too cold tonight to put it on.

What are your guys thoughts? I am hoping it is the fuel filter and that will fix the cranking and the rough idling. It has been feeling doggy too when I mash it to the floor so I hope that is the problem!!! it only has 97k on it.

SON1C · March 5th, 2011, 09:15 PM

i don't think its the fuel filter.

02GreyStallion · March 5th, 2011, 09:25 PM

My thought on the slow start is Plug Wires. My stang did that and then I picked up the MSD wires from AM and it fires right up

Mr. Red Pony · March 5th, 2011, 09:37 PM

Sounds like the coil pack is building excess internal resistance during the cold.

You you have a was to measure electrical resistance?

If so, I'll go more into detail. If not; get one and then I'll go into detail..

Mr. Red Pony · March 5th, 2011, 09:39 PM

After re-reading, I think it could be the IAT or ECT sensors are acting up.

Codeman · March 5th, 2011, 10:19 PM

I will have to check coil resistance later. I just went out and sucked it up and put my new fuel filter in at 0 degrees F. HAHA. Well my old one I shook up and poured fuel out and it was full of crap!!! I started my car and it idles much smoother now and the AF ratio looks much better. I will have to wait and see in the morning if it works better. Lets hope.

I replaced plug wires last year but they were some cheap ones.

Mr. Red Pony · March 5th, 2011, 10:46 PM

Secondary resistance should be 8k ohm to 14.5k ohm per coil. Mine was getting over 20k ohms of resistance at just below freezing.

March 5th, 2011, 09:13 PM	#1
Codeman Hardcore Enthusiast Join Date: Nov 2007 Location: North Dakota Posts: 2,933 iTrader: 1 reviews	My car's been acting up. Ok well my car has been acting up for awhile now. It cranks over for a long time when it has been sitting over night before starting. It is colder outside too right now in the 20s or so. I have a brand new battery that I put in last year, I cleaned the posts and clamps just incase. It just seems to me that it cranks and cranks and then like partially starts and then barely fires and will start up. It only happens over night. I was thinking maybe a bad check ball in the fuel pump but that should not matter, I have tried cycling the key twice to prime it and it did the same thing. Also today I was driving around and it started idling really rough. It felt like a broken motor mount. But when I would give it gas it would run fine. I didn't feel a miss once I put my foot on the gas. And I noticed that when it was idling rought the AF ratio on my wideband would slowly go lean to sometimes 16:1 or more then quickly drop back to rich. I am wondering if I don't have some 02 sensors that are acting up. I just bought a fuel filter it has been at least 2 years since I put one on so I figured I would try that first. It was just too cold tonight to put it on. What are your guys thoughts? I am hoping it is the fuel filter and that will fix the cranking and the rough idling. It has been feeling doggy too when I mash it to the floor so I hope that is the problem!!! it only has 97k on it. __________________ UDP, CAI, True Duals, LTs, 91 Tune from TT, 3.73 gears, Tlok,Windstar upper, GT TB, Ported lower, Comp 218/226 cam, FRPP C Springs, J&M LCA, Tokico Blue shocks and struts, and J&M Full Length Subframe Connectors

March 5th, 2011, 09:15 PM	#2
SON1C Run ur car, not ur mouth. 2003 Sonic Blue 4.6L Join Date: Jul 2010 Location: Northern Virginia Posts: 4,055 Blog Entries: 1 iTrader: 3 reviews	i don't think its the fuel filter. __________________ 238rwhp/263rwtq Drew's Build Thread

March 5th, 2011, 09:25 PM	#3
02GreyStallion Regular 2002 v6 Mustang Join Date: Nov 2009 Location: Chesterton, Indiana Posts: 414 iTrader: 0 reviews	My thought on the slow start is Plug Wires. My stang did that and then I picked up the MSD wires from AM and it fires right up __________________ - Mac 2.5" with 3 " duals - AM Cold Air Intake - Clear Fog Lights - Mach I Chin Spoiler - Mach I Grille Delete - MSD Plug Wires - New Clutch - Window Tint (Future) - Tokico Blues (Cut Springs)

March 5th, 2011, 09:37 PM	#4
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,788 iTrader: 10 reviews	Sounds like the coil pack is building excess internal resistance during the cold. You you have a was to measure electrical resistance? If so, I'll go more into detail. If not; get one and then I'll go into detail.. __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

March 5th, 2011, 09:39 PM	#5
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,788 iTrader: 10 reviews	After re-reading, I think it could be the IAT or ECT sensors are acting up. __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

March 5th, 2011, 10:19 PM	#6
Codeman Hardcore Enthusiast Join Date: Nov 2007 Location: North Dakota Posts: 2,933 iTrader: 1 reviews	I will have to check coil resistance later. I just went out and sucked it up and put my new fuel filter in at 0 degrees F. HAHA. Well my old one I shook up and poured fuel out and it was full of crap!!! I started my car and it idles much smoother now and the AF ratio looks much better. I will have to wait and see in the morning if it works better. Lets hope. I replaced plug wires last year but they were some cheap ones. __________________ UDP, CAI, True Duals, LTs, 91 Tune from TT, 3.73 gears, Tlok,Windstar upper, GT TB, Ported lower, Comp 218/226 cam, FRPP C Springs, J&M LCA, Tokico Blue shocks and struts, and J&M Full Length Subframe Connectors

March 5th, 2011, 10:46 PM	#7
Mr. Red Pony Resident badass 01 Built V6 (3.9) 13.91 @ 99.1 N/A Join Date: Jan 2010 Location: Lawton, Oklahomo Posts: 6,788 iTrader: 10 reviews	Secondary resistance should be 8k ohm to 14.5k ohm per coil. Mine was getting over 20k ohms of resistance at just below freezing. __________________ 271rwhp N/A V6 The Name is Danny. I'm a GM Technician. Suck it.

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