stall/stumble
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
stall/stumble
Really need some help here guys.
My 86 died a month ago. Wouldn't crank at all-finally found out it was the 5 amp fuse behind the info center in the dash...replaced it and it cranks and ildes fine. BUT pulling out of the drive it stumbles when I hit the gas like I am use too. If I let off it will smooth a bit and then if I slowly get into the gas it will do its best to maintain speed. I have already tried everything ie.. new fuel pump, new fuel filter, noid light on the injector harness. My Sunpro fuel pressure gauge says the pump starts (ignition on) about 20#s and maintains with the car cranked a little above 30#s is this normal??
What should the pressure be?
One more thing not to be a pain but when I check the aldl via jumping it I was getting some codes but I cannot figure how to decypher them. How do you get 12 from 1 flash pause 2 flashes long pause and so on. I got (after the handshake) 4 flashes pause 3 flashes (what code is that and how do I count it???)
My 86 died a month ago. Wouldn't crank at all-finally found out it was the 5 amp fuse behind the info center in the dash...replaced it and it cranks and ildes fine. BUT pulling out of the drive it stumbles when I hit the gas like I am use too. If I let off it will smooth a bit and then if I slowly get into the gas it will do its best to maintain speed. I have already tried everything ie.. new fuel pump, new fuel filter, noid light on the injector harness. My Sunpro fuel pressure gauge says the pump starts (ignition on) about 20#s and maintains with the car cranked a little above 30#s is this normal??
What should the pressure be?
One more thing not to be a pain but when I check the aldl via jumping it I was getting some codes but I cannot figure how to decypher them. How do you get 12 from 1 flash pause 2 flashes long pause and so on. I got (after the handshake) 4 flashes pause 3 flashes (what code is that and how do I count it???)
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Did a quick search for you:
http://forums.corvetteforum.com/c4-t...code-43-a.html
Your fuel pressure seems way low..either you gage is bad or ...fuel pressure regulator or pulsator module may have issues.....do a search for fuel pressure tests.
http://forums.corvetteforum.com/c4-t...code-43-a.html
Your fuel pressure seems way low..either you gage is bad or ...fuel pressure regulator or pulsator module may have issues.....do a search for fuel pressure tests.
Last edited by engle1147; Nov 9, 2008 at 08:25 PM.
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
I really really appreciate the reply, how do you figure out which code it is by the flashes?? I am so lost my wife has 2 degrees in comp programming and neither one of us can figure out how you get the numbers by the flashes. Any help??
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
I have a computer I hook up to the car to read my codes...it also give you real time values for each sensor's reading.
If I remember right the after the hand shake you get a one or series of flashes then a pause, this it the first digit. Then you get another single or series of flashes (1-9) this is the second digit. Then you should get another pause and the next code will show if you have others......etc
Your '86 has a OBD1 computer in it.......Walmart sells code readers for cheap.....but make sure you get a reader that does OBD1. Most for sale now a days are for OBD2...some do both. There is all kinds of software/freeware out there that you can download onto a laptop to read your cars codes.....but you'll need an interface cable for it to work.
If I remember right the after the hand shake you get a one or series of flashes then a pause, this it the first digit. Then you get another single or series of flashes (1-9) this is the second digit. Then you should get another pause and the next code will show if you have others......etc
Your '86 has a OBD1 computer in it.......Walmart sells code readers for cheap.....but make sure you get a reader that does OBD1. Most for sale now a days are for OBD2...some do both. There is all kinds of software/freeware out there that you can download onto a laptop to read your cars codes.....but you'll need an interface cable for it to work.
Last edited by engle1147; Nov 9, 2008 at 08:40 PM.
Pro
Joined: Jun 2007
Posts: 626
Likes: 2
From: Coquitlam British Columbia
On my 1990 when checking codes...code 12 will flash(meaning all is okay if no bad codes)---1 long--2 short..this will happen 3 times in sequence.If there is a bad code after the 3 flashes of 12 the fault code will flash(e.g. 42) 4 long---2 short and will repeat 3 times. If no other bad codes; then will finish with 3 times code 12 flash to close the communications.
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
I have a computer its just at my work and didnt feel like going for it today wanted to learn it the roots way. Thanks so much for the explain on the codes that really does help I kept tellin my buddy I thought it was the Mass air flow sensor or I had bad gas. Would the knock sensor be sending that code if I had crappy arab gas?? The car ran fine when I filled up the last time before hurricane Ike and then I filled up afterwards at a BP next to the house we just bought and my truck and the vette and my scout have been acting up. Will that do it to your knowledge??
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
On my 1990 when checking codes...code 12 will flash(meaning all is okay if no bad codes)---1 long--2 short..this will happen 3 times in sequence.If there is a bad code after the 3 flashes of 12 the fault code will flash(e.g. 42) 4 long---2 short and will repeat 3 times. If no other bad codes; then will finish with 3 times code 12 flash to close the communications.
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Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
I have a computer its just at my work and didnt feel like going for it today wanted to learn it the roots way. Thanks so much for the explain on the codes that really does help I kept tellin my buddy I thought it was the Mass air flow sensor or I had bad gas. Would the knock sensor be sending that code if I had crappy arab gas?? The car ran fine when I filled up the last time before hurricane Ike and then I filled up afterwards at a BP next to the house we just bought and my truck and the vette and my scout have been acting up. Will that do it to your knowledge??
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Last edited by engle1147; Nov 9, 2008 at 09:35 PM. Reason: +ed pic
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
Engle sir you are officially my new bestest friend, lemme know when your birthday is and i send ya some of my (Lowndes County) famous hot sauce. thank you so for all your help if I can figure this dang site out I'll add ya as a friend and help you anyway I can I'm a recent Ford convert so I'm stumblin a little just like the ole car I have fell in love with.
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
pressure
well I did unplug the vaccum line on the regulator and I'm still at 20#s with the key on and 30#s with the engine running when I give it some gas the guage drops a pound or two. Could this be the regulator or an injector?? Still searchin. Thank you guys for helpin and suggestin its really getting my brain movin towards the cure
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
well I did unplug the vaccum line on the regulator and I'm still at 20#s with the key on and 30#s with the engine running when I give it some gas the guage drops a pound or two. Could this be the regulator or an injector?? Still searchin. Thank you guys for helpin and suggestin its really getting my brain movin towards the cure
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
thanks again gonna sleep on this one, I scratched my head for a month on the non starting issue and got that one nailed down so I refuse surrender. I know it is going to be something terribly simple And after 30 years die hard Ford man I will not quit on my lil chevy.
Pro
Joined: May 2006
Posts: 637
Likes: 0
No change after the new fuel pump?
What brand fuel pump, bought where?
If fuel pump ok, then it´s probably FPR.
If you really have a code 43, it says electronic spark control.
Check the wiring on the whole distribution system.
Thread Starter
Cruising
Joined: Jul 2008
Posts: 13
Likes: 0
From: Columbus Ms
well its a cheapo fuel pump i bought from AutoZone, I honestly do not believe it is the pump I'm leaning more towards the regulator as Engle suggested havent had the chance since sunday to research more. Thank you guys for all the help I'm gonna get back on it. I think both of you are on the money though and the regulator is my enemy. Should I go with an OEM type or buy an adjustable as I am planning on mods as soon as she gets back on the road healthy have already restored the interior and other items and wouldnt mind a little extra GO.
Thanks again to all
a
Thanks again to all
a
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
well its a cheapo fuel pump i bought from AutoZone, I honestly do not believe it is the pump I'm leaning more towards the regulator as Engle suggested havent had the chance since sunday to research more. Thank you guys for all the help I'm gonna get back on it. I think both of you are on the money though and the regulator is my enemy. Should I go with an OEM type or buy an adjustable as I am planning on mods as soon as she gets back on the road healthy have already restored the interior and other items and wouldnt mind a little extra GO.
Thanks again to all
a
Thanks again to all
a
Advanced
Joined: Apr 2003
Posts: 60
Likes: 0
From: Cedar Park TX
Code 43
GeorgeC
