06-05-2017, 11:16 PM
|
#1
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
05 4.7 V8 has intermittent extended crank time on cold/hot starts.
Hey everyone, I'm new to the forum here and new to Toyotas as well which is why I need some extra help.
The problem is that my 4runner has long crank time intermittently. It doesn't matter whether it is hot or cold, or if it is a cold start or starting it within five minutes of turning it off I will either have a super quick start or a super long start. The longest it has taken is probably 7 seconds of cranking before it will start. It always starts, but its starting to worry me because I don't want something to fail and leave me stranded.
The battery tests good, the alternator tests good, the starter is cranking strong, I have tested the fuel pressure regulator with a vacuum gauge and it holds pressure, and the fuel pump relay is good.
I hooked up a fuel pressure gauge today and got these results. When I turn the key to on (not starting the vehicle) it sits at 0. When the vehicle is started the pressure goes up to 42 psi. After turning off the car the pressure drops to 38 psi, and stays above 35 psi for 5 minutes. I am used to GM vehicles, which prime the whole fuel system when the key turns to on. Is it normal that my 4runner stays at 0 when I turn the key to on? Shouldn't turning the key prime the fuel rails and get the system up to pressure?
If the pump is operating how it is supposed to, do you have any ideas of what could be wrong? Can the fuel pressure damper fail? Could it be a bad ground like 03-04 Tacomas had a problem with?
Another thing to note is that there are no fault codes that come on while driving, BUT if I turn the key to on, wait 10 seconds, then repeat twice, the ECU throws 3 fault codes. The codes are P0441 (Evap system incorrect purge flow), P0455 (Large evap system leak), and P0456 (Small evap system leak. These only come on if I "prime" the system 3 times and then start the vehicle. I get the codes as well as the VSC and traction control light. When it happens I am able to clear them and they don't come back on until I do what is described above.
I've looked around the forums and haven't found anything quite like this. Any help is greatly appreciated. Thanks!
Last edited by Utah_4runner; 06-06-2017 at 07:01 AM.
|
|
Reply With Quote
|
06-06-2017, 08:22 AM
|
#2
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Note: I also just did a 3 part sea foam treatment, and then replaced the spark plugs with NGK laser iridiums.
|
|
Reply With Quote
|
06-06-2017, 09:13 AM
|
#3
|
|
Senior Member
|
|
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
|
Senior Member
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
clean the MAF and throttle body.. check wiring.. also could be Crank position sensor. disconnect battery for a few hours and reset the computer. Id start with that easier stuff.
|
|
Reply With Quote
|
06-06-2017, 09:50 AM
|
#4
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Quote:
Originally Posted by Billynath1988
clean the MAF and throttle body.. check wiring.. also could be Crank position sensor. disconnect battery for a few hours and reset the computer. Id start with that easier stuff.
|
I'll try those out in a few hours and let you know if there is any progress. The MAF seemed really clean when I looked at it a couple of weeks ago, I'll clean it anyway.
|
|
Reply With Quote
|
06-06-2017, 08:01 PM
|
#5
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Today I cleaned the throttle body, cleaned the MAF sensor, and had the battery disconnected for several hours to let the computer reset. The first few starts after that were great, but I'm right back to where I was with intermittent long cranking. I have never had any of the symptoms of a failing camshaft or crankshaft position sensor, so I really don't think it is that... plus those are too hard to get to anyway. Any other ideas of things I could try? Does anyone know if it is normal for the fuel rail pressure to be at 0 when I turn the key to on multiple times?
|
|
Reply With Quote
|
06-06-2017, 08:23 PM
|
#6
|
|
Senior Member
|
|
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
|
Senior Member
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
hm.. not sure about the fuel pressure reading.. run a load test on the battery?
|
|
Reply With Quote
|
06-06-2017, 08:37 PM
|
#7
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Quote:
Originally Posted by Billynath1988
hm.. not sure about the fuel pressure reading.. run a load test on the battery?
|
Battery came out good as well. I think it would have to be the fuel pump or a bad ground possibly. Have you, or anyone else ever had to replace a fuel pump? What were your symptoms with the 4runner?
|
|
Reply With Quote
|
06-06-2017, 08:49 PM
|
#8
|
|
Senior Member
|
|
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
|
Senior Member
Join Date: Aug 2012
Location: longisland ny
Age: 36
Posts: 1,252
|
I never really had this issue on my 05 v8. I know when the batterys get weak it makes the truck do weird stuff. I personally haven't had to or seen anyone else replace a fuel pump on these. You said it throws a code right? I do know these trucks can have evap system issues if you overfill the tank to much and it leaks fuel into the charcoal canister but Idk if this would be a symptom of that or not. .. check PCV valve.. 02 sensors.. ect..
|
|
Reply With Quote
|
06-06-2017, 09:39 PM
|
#9
|
|
Elite Member
|
|
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,902
|
|
Elite Member
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,902
|
Every now and then the 4th gen cranks a little longer that it usually does... I never did figure out why. It's somewhat present on other vehicles I've worked on as well, could just be an anomaly where the ECM didn't like the crank/cam correlation and wanted another revolution to make sure... hard to say unless it's consistent.
|
|
Reply With Quote
|
06-06-2017, 09:48 PM
|
#10
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Yeah, it throws three codes, but not while operating, just if I triple prime the fuel system (which I just found doesn't work) without starting the vehicle. I didn't know that the newer 4runners had a fuel pump access port until now, so I pulled up the carpet and listened carefully as I had someone turn the key to on, and then start it. It doesn't start pushing fuel until it goes on, so it doesn't prime anything like it is supposed to. I think i'll replace the fuel pump and see if it fixes it. Hopefully that'll fix it.
|
|
Reply With Quote
|
06-06-2017, 09:50 PM
|
#11
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Quote:
Originally Posted by BlackWorksInc
Every now and then the 4th gen cranks a little longer that it usually does... I never did figure out why. It's somewhat present on other vehicles I've worked on as well, could just be an anomaly where the ECM didn't like the crank/cam correlation and wanted another revolution to make sure... hard to say unless it's consistent.
|
Sorry BlackWorksInc, I didn't see your post until after I just posted. It is off and on, but cranks long at least daily, and just seems too long at times to be an anomaly. It cranks long enough at times that I feel like i'm in some old beater!
|
|
Reply With Quote
|
06-06-2017, 10:27 PM
|
#12
|
|
Elite Member
|
|
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,902
|
|
Elite Member
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,902
|
Quote:
Originally Posted by Stephen5217
Sorry BlackWorksInc, I didn't see your post until after I just posted. It is off and on, but cranks long at least daily, and just seems too long at times to be an anomaly. It cranks long enough at times that I feel like i'm in some old beater!
|
Hmm... how's the starter sound?
|
|
Reply With Quote
|
06-06-2017, 11:39 PM
|
#13
|
Member
|
|
Join Date: Apr 2017
Location: Colorado
Posts: 50
|
|
Member
Join Date: Apr 2017
Location: Colorado
Posts: 50
|
Easily hot wire the fuel pump at the relay so it runs with the key on. Try to duplicate your cranking issue. But if it cranks long when the manifold is still under pressure, I'd doubt its fuel related. I'd say it has to do with your codes that you pulled. That evap canister uses engine vacuum to purge fuel vapors. If there is a vacuum leak anywhere in that system, it will start slow and crank long. Look over the part and any other vacuum hoses and connections that could leak. You could also try and block the evap system off from the engine, it may be the evap canister itself. Look over the gas cap for a proper seal and fit.
Last edited by Phils4th; 06-06-2017 at 11:49 PM.
|
|
Reply With Quote
|
06-07-2017, 01:49 AM
|
#14
|
Member
|
|
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
|
Member
Join Date: May 2017
Location: Utah
Posts: 108
Real Name: Stephen
|
Quote:
Originally Posted by BlackWorksInc
Hmm... how's the starter sound?
|
The Starter is cranking very strong.
Quote:
Easily hot wire the fuel pump at the relay so it runs with the key on. Try to duplicate your cranking issue. But if it cranks long when the manifold is still under pressure, I'd doubt its fuel related. I'd say it has to do with your codes that you pulled. That evap canister uses engine vacuum to purge fuel vapors. If there is a vacuum leak anywhere in that system, it will start slow and crank long. Look over the part and any other vacuum hoses and connections that could leak. You could also try and block the evap system off from the engine, it may be the evap canister itself. Look over the gas cap for a proper seal and fit.
|
What do you mean when you say hot wire the fuel pump? I'll have to dig into the evap system some more I guess. My OCD does make me bump the gas up to the next dollar, so I could have overfilled at some point. Anyone have common failure points with the evap system where I could start?
|
|
Reply With Quote
|
06-07-2017, 01:59 AM
|
#15
|
Member
|
|
Join Date: Oct 2016
Location: Bakersfield CA
Posts: 44
|
|
Member
Join Date: Oct 2016
Location: Bakersfield CA
Posts: 44
|
Do a compression test on each and get back to us with the results.
__________________
2008 Sr5 V6 4x4
Daystar lift
1"body lift
fj trail edition wheels
falken wildpeaks
|
|
Reply With Quote
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is On
|
|
|
|