efi questions - The 1947 - Present Chevrolet & GMC Truck Message Board Network

slow69 · 06-11-2002, 01:27 AM

I have two problems that I need some help on.

1. I have a 95 c3500 dually that has a throttle body fuel injection system. This truck runs like a dream but something has happened twice that is driving me nuts. I will start the truck up and say move it about 200 ft and turn it off. The next time I get in it, it won't start. I let it set for a couple of minutes and bam... starts right up. I've replaced everything I can think of and wanted to ask before I took it in to get a diagnostic.

2. I ran across a 90 chevy van with a efi 350 throttle body as well. I would like to take all of the efi stuff out of it and place it in my 69. Will this pose any problems? Is it worth the wiring mess?

Thanks alot. I hope someone out there can help me out.
-slow

Mike C · 06-11-2002, 08:57 AM

Your dually might have a bad temp sender that reads incorrectly. This might not activate the cold start circuit after a start up/shut down. The 90 efi setup from the 350 will work if you modify the center intake bolt holes by grinding them to line up with the heads.

slow69 · 06-11-2002, 10:31 AM

thanks mike,
I will replace the temp sender and let you know if it works. It may take a while because it has only happened twice in like 5 years. I just hate when unexplained things happen so I'd like to fix the problem before it leaves me stranded.
Thanks again,
Slow

Wasted Income · 06-11-2002, 08:21 PM

Please, please, please, please, please, please, please, please, please, please, use a stand alone wiring harness from Ron Francis or Painless Wiring, or Street and Performance. The $600 or so pricetag may seem steep, but the 3 years worth of headaches that my '94 L05 with '90 TBI gave me. We went through and intergrated all of the newer wiring to the original '69 harness. It looked totally clean (even had the ALDL and the check engine light in the gauge cluster), but worked like total crap. I think that I replaced every sensor twice, the computer, the chip, the injectors, yada yada yada. Not a cheap deal by any means. I eventually ended up swaping out the EFI and going with a Holley carb.

Don't get me wrong.......I'm not against EFI. In fact, I plan on an LS1 or LS6 in my '67, but you can bet it will be a pre-fabbed wiring harness that's used.

Good luck,
-Jeff

slow69 · 06-11-2002, 08:46 PM

jeff,

are you sure... j/k. i will look into buying one. I'm sorry you had so many problems with yours. But if it is such a pain in the rear, why do it... the fuel savings aren't that great. I may just wait until I get an LT-1.
Thanks,
slow

Wasted Income · 06-12-2002, 06:52 PM

I'm not sure why, just cuz it's cool I guess. It's funny seeing the look on non-car people's faces when you tell them that it's fuel injected. Plus the ease of starting and smooth as glass idle were a bonus, esp for a daily driver (which it was at the time). My problems resided somewhere in the mid to upper powerband. Long story, big mess, but I'd do it again in a "heartbeat" (the correct way of course)

Hmmm.....LT1 over an LO5?

Gee that's a tough one

slow69 · 06-12-2002, 07:56 PM

yah... but the wiring kits are so expensive. I was checking ron francis and painless and they are a lot. I might have to wait for a while and save up. The LT-1 has got to be my dream engine... easily converted to LT-4... Awesome engine.... Thanks for all of your help.
-slow

PushinPebbles · 06-12-2002, 08:03 PM

I'd say the problem w/ ur dually is the fuel regulater................
but some say im crazy JACK

lukecp · 06-12-2002, 09:12 PM

In a Painless Wiring flyer i got when i ordered some stuff from Summit, i saw a adaptor plate desinged to mount the TBI throttle body on a Quadrajet or holley-style intake. Then, you wouldn't have to grind out any bolt holes. Good luck!

blue_69 · 06-12-2002, 09:42 PM

Holly makes an adapter to put a tbi on an 4 barrel intake its part#17-45 do a manufacturer part # search on summit and also gm put them on big blocks you might find one on ebay. You can find good tbi info at www.thirdgen.org

Good luck jason

superchevy · 06-12-2002, 10:45 PM

Here's a link to pics of my truck using an Edelbrock Performer carb intake with the Holley tbi adapter. SC

http://www.imagestation.com/album/pi...?id=4291867497

06-11-2002, 08:57 AM	#2
Mike C Registered User Join Date: Dec 1999 Location: Austin, TX, USA Posts: 7,723	Your dually might have a bad temp sender that reads incorrectly. This might not activate the cold start circuit after a start up/shut down. The 90 efi setup from the 350 will work if you modify the center intake bolt holes by grinding them to line up with the heads. __________________ 44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax

06-11-2002, 08:21 PM	#4
Wasted Income Boosted Member Join Date: May 2002 Location: Mackinaw, IL Posts: 2,200	Please, please, please, please, please, Please, please, please, please, please, please, please, please, please, please, use a stand alone wiring harness from Ron Francis or Painless Wiring, or Street and Performance. The $600 or so pricetag may seem steep, but the 3 years worth of headaches that my '94 L05 with '90 TBI gave me. We went through and intergrated all of the newer wiring to the original '69 harness. It looked totally clean (even had the ALDL and the check engine light in the gauge cluster), but worked like total crap. I think that I replaced every sensor twice, the computer, the chip, the injectors, yada yada yada. Not a cheap deal by any means. I eventually ended up swaping out the EFI and going with a Holley carb. Don't get me wrong.......I'm not against EFI. In fact, I plan on an LS1 or LS6 in my '67, but you can bet it will be a pre-fabbed wiring harness that's used. Good luck, -Jeff __________________ 1972 2wd K/5 Blazer Turbocharged 370 LSx - 941 rwhp / 1093 rwtq 1969 Chevy K-10 L33 5.3 / 4L80E / NP241 / 4" lift 1964 Buick Skylark Twin TURBO 383 LS pro-touring project 2014 VW Passat TDI - Daily Driver Turbo diesel 2015 Sierra Denali HD Duramax Turbo diesel 2023 Ford Explorer ST - Twin Turbskis 2023 Ford F150 RCSB - Whipple Supercharged 2017 Polaris RZR Turbo 2014 Nor-Tech Center Console - Twin Supercharged Outboards *TURBO ALL THE THINGS!!*

06-12-2002, 06:52 PM	#6
Wasted Income Boosted Member Join Date: May 2002 Location: Mackinaw, IL Posts: 2,200	Why? I'm not sure why, just cuz it's cool I guess. It's funny seeing the look on non-car people's faces when you tell them that it's fuel injected. Plus the ease of starting and smooth as glass idle were a bonus, esp for a daily driver (which it was at the time). My problems resided somewhere in the mid to upper powerband. Long story, big mess, but I'd do it again in a "heartbeat" (the correct way of course) Hmmm.....LT1 over an LO5? Gee that's a tough one __________________ 1972 2wd K/5 Blazer Turbocharged 370 LSx - 941 rwhp / 1093 rwtq 1969 Chevy K-10 L33 5.3 / 4L80E / NP241 / 4" lift 1964 Buick Skylark Twin TURBO 383 LS pro-touring project 2014 VW Passat TDI - Daily Driver Turbo diesel 2015 Sierra Denali HD Duramax Turbo diesel 2023 Ford Explorer ST - Twin Turbskis 2023 Ford F150 RCSB - Whipple Supercharged 2017 Polaris RZR Turbo 2014 Nor-Tech Center Console - Twin Supercharged Outboards *TURBO ALL THE THINGS!!*

06-12-2002, 08:03 PM	#8
PushinPebbles My dad's 68 Join Date: May 2002 Location: VA Posts: 444	I'd say the problem w/ ur dually is the fuel regulater................ but some say im crazy JACK __________________ Jack M. 67 C-10 SWB 355 built T-350 tranny hurst shifter 17x8in KMC's on michelins, clear tails and back up lights slammedUPDATE i have decided on my bag setup and will post further info when i recieve all the parts **************************** 88 1/2 ton suburban 4x4 350/700R-4having a 9 in lift w/ 38 in tires 4 12 inch Lightning Audios *************************** 87 silverado 3/4ton jacked up 10-12 inches black and rubberized bed coating 35 in michelans ************************** Dad's truck 68 C-10 stepside, 468 BB, tubbed, weld wheels, Nason black,lots more **************************** grand dads truck 68 C-10 stepside fuel inj. 350/700R-4soon in audi silver **************************** 84 toyota pickup 22R 5 speed 2WD slammed, shaved and all the body lines filled w/ buickGN scoop,bout to be sprayed in 2003 mustang green metallic w/ silver flames **************************** S/N=BIGGYTYME@aol.com (hydros) "No fat chics, truck will scrape"

06-12-2002, 09:12 PM	#9
lukecp Formerly yellow72custom Join Date: May 2001 Location: Austin, TX Posts: 7,531	You can get a TBI adaptor plate In a Painless Wiring flyer i got when i ordered some stuff from Summit, i saw a adaptor plate desinged to mount the TBI throttle body on a Quadrajet or holley-style intake. Then, you wouldn't have to grind out any bolt holes. Good luck! __________________ '72 Chevy C10 Mild 350/TH350/3.07. Ochre/White. Old high school ride. '70 GMC C2500 '62 327 4bbl/SM465/4.56-geared Dana 60. White/White. Project or parts truck. '97 Saturn SL DD. 1.9/5-speed. 40+ highway mpg

06-11-2002, 01:27 AM	#1
slow69 Registered User Join Date: Dec 2000 Location: Flagstaff, AZ Posts: 140	efi questions I have two problems that I need some help on. 1. I have a 95 c3500 dually that has a throttle body fuel injection system. This truck runs like a dream but something has happened twice that is driving me nuts. I will start the truck up and say move it about 200 ft and turn it off. The next time I get in it, it won't start. I let it set for a couple of minutes and bam... starts right up. I've replaced everything I can think of and wanted to ask before I took it in to get a diagnostic. 2. I ran across a 90 chevy van with a efi 350 throttle body as well. I would like to take all of the efi stuff out of it and place it in my 69. Will this pose any problems? Is it worth the wiring mess? Thanks alot. I hope someone out there can help me out. -slow

06-11-2002, 10:31 AM	#3
slow69 Registered User Join Date: Dec 2000 Location: Flagstaff, AZ Posts: 140	thanks mike, I will replace the temp sender and let you know if it works. It may take a while because it has only happened twice in like 5 years. I just hate when unexplained things happen so I'd like to fix the problem before it leaves me stranded. Thanks again, Slow

06-11-2002, 08:46 PM	#5
slow69 Registered User Join Date: Dec 2000 Location: Flagstaff, AZ Posts: 140	jeff, are you sure... j/k. i will look into buying one. I'm sorry you had so many problems with yours. But if it is such a pain in the rear, why do it... the fuel savings aren't that great. I may just wait until I get an LT-1. Thanks, slow

06-12-2002, 07:56 PM	#7
slow69 Registered User Join Date: Dec 2000 Location: Flagstaff, AZ Posts: 140	yah... but the wiring kits are so expensive. I was checking ron francis and painless and they are a lot. I might have to wait for a while and save up. The LT-1 has got to be my dream engine... easily converted to LT-4... Awesome engine.... Thanks for all of your help. -slow

06-12-2002, 09:42 PM	#10
blue_69 someday Join Date: Dec 2001 Location: canastota,new york Posts: 629	Holly makes an adapter to put a tbi on an 4 barrel intake its part#17-45 do a manufacturer part # search on summit and also gm put them on big blocks you might find one on ebay. You can find good tbi info at www.thirdgen.org Good luck jason __________________ Click Here to search ebay for all 67-72 parts My 72 CST blazer build 72 CST Blazer 4x4 67 2wd swb ( project onion crate ) 86 4x4 lwb plow truck 40 x 60 foot barn to work on all this stuff

06-12-2002, 10:45 PM	#11
superchevy Got big-block? Join Date: Jul 2000 Location: Austin, Texas Posts: 2,453	Here's a link to pics of my truck using an Edelbrock Performer carb intake with the Holley tbi adapter. SC http://www.imagestation.com/album/pi...?id=4291867497 __________________ '68 CST SWB factory 396/T400 buddy buckets, a/c, ps, pb '72 Corvette convertible 454/4spd/ac, ps, pb '73 GMC Sierra Grande short wide 454/T400 ps, pb, ac '77 K5 Blazer black on red, 350/T350/NP205 ps, pb, ac all original '78 GMC Sierra Classic short wide 454/T400 ps, pb, ac '72 GMC Sprint SP454. 1 of 38 built. '73 GMC Sprint SP454. 1 of 71 built. '75 GMC Sprint SP454. 1 of 25 built. SOLD! '72 GMC K25 4x4 468/4L80e/NP205 build thread http://67-72chevytrucks.com/vboard/s...23#post4324423 SOLD!'55 Chevy gasser 496/4spd build thread http://67-72chevytrucks.com/vboard/s...96#post4324396



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