hard to start
Thread Starter
Burning Brakes
Joined: Dec 2005
Posts: 831
Likes: 2
From: Silver Spring, MD
hard to start
Hey guys,
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
Hey guys,
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
Try this - turn the key on, letting the fuel pump run for its 2 secs, turn the key off, wait for a bit (30 secs), then try turn it on again, not start, just on to hear the pump run again. This should fill the rail with fuel. Now, try to start it. If it starts right up, something is emptying the rail. Could be an injector, could be the FPR, could also be the fuel pump check valve. The pinch test will isolate the issue.
Fuel pressure checks then pinch tests will often lead to the problem id, thus solution. A couple guys on here have troubleshooting flow diagrams to help with this sort of issue. Good luck!
Thread Starter
Burning Brakes
Joined: Dec 2005
Posts: 831
Likes: 2
From: Silver Spring, MD
Check your fuel pressure...could be a couple things with fuel delivery, leaking injectors, weakened fuel pump, fuel pressure regulator. Mine acts similar and I believe I have a leaky injector which is leaving my fuel rail empty. When cold, the empty fuel rail has to be filled and pressurized by the pump. May take a couple turns of the key to get the rail filled.
Try this - turn the key on, letting the fuel pump run for its 2 secs, turn the key off, wait for a bit (30 secs), then try turn it on again, not start, just on to hear the pump run again. This should fill the rail with fuel. Now, try to start it. If it starts right up, something is emptying the rail. Could be an injector, could be the FPR, could also be the fuel pump check valve. The pinch test will isolate the issue.
Fuel pressure checks then pinch tests will often lead to the problem id, thus solution. A couple guys on here have troubleshooting flow diagrams to help with this sort of issue. Good luck!
Try this - turn the key on, letting the fuel pump run for its 2 secs, turn the key off, wait for a bit (30 secs), then try turn it on again, not start, just on to hear the pump run again. This should fill the rail with fuel. Now, try to start it. If it starts right up, something is emptying the rail. Could be an injector, could be the FPR, could also be the fuel pump check valve. The pinch test will isolate the issue.
Fuel pressure checks then pinch tests will often lead to the problem id, thus solution. A couple guys on here have troubleshooting flow diagrams to help with this sort of issue. Good luck!
WOW! That seems to be just what is happening. Just went out and tested as described. If anyone has the troubleshooting flow diagram, i would certainly apprecoate it. Thank you very much for the info!
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
3 cranks? What are cranks? revolutions of the engine or holding the key on for 10 to 15 secods or what? How old is the tune up (miles and years ago)and the the ecu air and water temp sensors read correctly if yes did you determine that with a scan tool as dash readings are meaningless.
Thread Starter
Burning Brakes
Joined: Dec 2005
Posts: 831
Likes: 2
From: Silver Spring, MD
3 cranks? What are cranks? revolutions of the engine or holding the key on for 10 to 15 secods or what? How old is the tune up (miles and years ago)and the the ecu air and water temp sensors read correctly if yes did you determine that with a scan tool as dash readings are meaningless.
thx
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
When cranking i am holding the key for about 5-10 seconds. i am not sure about the tune but will check with his regular mechanic. I think he gave it minor tune up when purchased. i am sure it has been under a scan. Of course mine will not work. Need to get a hold of OBDI scanner and see what codes i may get. Again thanks for the info. I'll get as soon as take some readings.
thx
thx
A couple things...
I've got the same disorder...I hear its common with Bosch III replacement injectors. It can also come from a pump that allows fuel to back flow when sitting too long. That does not seem right because mine holds 40+ lbs for hrs..only loosing 5-8 lbs per hr after 3. After 6 hrs it'll still have 20+.
The eng temp sensor can cause some starting issues. It tells the ecm if CS is needed or not.
The fuel relay MIGHT be bad, forcing the fuel pump to get its power from its alternate source, oil pressure that comes from cranking several seconds.
When I'm facing a cold start, I turn key ON 2-3 seconds, crank 1 sec then off.
Turn key a 2nd time and it lites off instantly.
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
I have just learned to live with it...I turn on the key, let it prime, turn it off, wait for a couple, then crank her up.
Funny, I was just about ready to swap out my injectors for a set of the Bosch 3's. May have to rethink this if I have more of this to look forward to. One of the main benefits I'm hoping to achieve by changing them is a better startup response.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
I have just learned to live with it...I turn on the key, let it prime, turn it off, wait for a couple, then crank her up.
Funny, I was just about ready to swap out my injectors for a set of the Bosch 3's. May have to rethink this if I have more of this to look forward to. One of the main benefits I'm hoping to achieve by changing them is a better startup response.
this is the very first comment about the Bosch being vulnerable to laws of physics, design, assembly, etc.
said all along -I am changing my original injectors on the 91 for the experience. car runs as good as new, far as I can tell, at 110K, starts "immediately" cold or hot. I figured it was a Corvette thing.
I am still confident that Jon's product is as good as he says, for the price. but I have heard comments here that after 2 yrs, no problem.
what about 20 yrs?
joe
***should add that I am changing injectors because I don't know the first 98k miles histoy of the car, as well as have a lot of time on my hands. also money. (hee hee)
Last edited by joe paco; Jun 28, 2011 at 08:42 AM. Reason: add comment
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Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
incredible! just ordered my III's yesterday. "to all things, there are contradictions and negatives, and compromises."
this is the very first comment about the Bosch being vulnerable to laws of physics, design, assembly, etc.
said all along -I am changing my original injectors on the 91 for the experience. car runs as good as new, far as I can tell, at 110K, starts "immediately" cold or hot. I figured it was a Corvette thing.
I am still confident that Jon's product is as good as he says, for the price. but I have heard comments here that after 2 yrs, no problem.
what about 20 yrs?
joe
***should add that I am changing injectors because I don't know the first 98k miles histoy of the car, as well as have a lot of time on my hands. also money. (hee hee)
this is the very first comment about the Bosch being vulnerable to laws of physics, design, assembly, etc.
said all along -I am changing my original injectors on the 91 for the experience. car runs as good as new, far as I can tell, at 110K, starts "immediately" cold or hot. I figured it was a Corvette thing.
I am still confident that Jon's product is as good as he says, for the price. but I have heard comments here that after 2 yrs, no problem.
what about 20 yrs?
joe
***should add that I am changing injectors because I don't know the first 98k miles histoy of the car, as well as have a lot of time on my hands. also money. (hee hee)
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
thanks
Racer
Joined: Apr 2011
Posts: 296
Likes: 1
From: Tipp City Ohio
Hey guys,
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
I am trying to help my father in law with his starting problem. He has a 1992 automatic. It takes three cranks and then turns over (when cold). When warm, it will turn right over. I've only changed the fuel filter thus far. The has been going on for over a year (i am visiting from out of state and trying to help now while in town). Just not sure whether the problem is electrical or fuel delivery>
Thx
So what did you find out?
Pro
Joined: Aug 2010
Posts: 617
Likes: 17
From: Hamilton Ontario
I've got the same disorder...I hear its common with Bosch III replacement injectors. It can also come from a pump that allows fuel to back flow when sitting too long. That does not seem right because mine holds 40+ lbs for hrs..only loosing 5-8 lbs per hr after 3. After 6 hrs it'll still have 20+.
When I'm facing a cold start, I turn key ON 2-3 seconds, crank 1 sec then off.
Turn key a 2nd time and it lites off instantly.
Mine works identical to above..no pressure issues--new fuel pump/filter and Bosch III injectors.
What causes those strange starting issues??
Racer
Joined: Oct 2006
Posts: 438
Likes: 14
From: Tucson/Santa Paula AZ/CA
2017 C4 of Year Finalist
I have not had that problem with my Bosch III's. Just the opposite, my engine fires after about 1.5seconds of cranking. Even my hot starts are better than they ever were with the stock Multechs.
Advanced
Joined: Jun 2010
Posts: 85
Likes: 1
From: Everett Washington
St. Jude Donor '11
hey Tony, re hard starting.... I have the 1990... you wrote me awhile back. I finally decided to take mine into a mechanic we put the gauge on it went from 40 lbs to about 10... but we find no rubber tubing in the fuel line in order to perform the pinch test, any ideas? I also use al_rosenzweig@msn.com
thanks for any help Tony
al
thanks for any help Tony
al
Advanced
Joined: Jun 2010
Posts: 85
Likes: 1
From: Everett Washington
St. Jude Donor '11
thanks Mike..... my mechanic looked at that but we didn't pull that fuel door we'll check it out thank you. Of the 3 items, fuel pressure regulator, injectors or fuel pump valve....any thoughts on the most likely culpret?
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
The fuel pressure regulators vacuum hose can leak fuel back into the engine and cause a rich condition when starting when cold because it is loaded up. Check to see if the vacuum line is wet.
Will start when it is hot because you need time for the leak down and it has not happened yet.
Will start when it is hot because you need time for the leak down and it has not happened yet.