Become a Fan!
Login
Username:

Password:

Remember Me

Lost Password?

Register now!
Main Menu
Who's Online
104 user(s) are online (63 user(s) are browsing Forums)

GRIS, more...
Guru Dictionary
Print in friendly format Send this term to a friend  TH350
Automatic Transmission - 3 Speed

1st Gear: 2.52
2nd Gear: 1.52
3rd Gear: 1.00

- Used in production GM models from 1969 thru 1979.
- 13 Bolt ...
Supporting Vendors
Platinum
Mid America Motorworks
Mid America Motorworks FREE CATALOG


Gold
FIC 770-888-1662


Registered Vendors
Guru Friends
Supporting Banners

TIRERACK.com - Revolutionizing Tire Buying


Shop for Winter Tires Now!




Support This Site
 Register To Post

joeld Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
On my 89, stock FPR and possibly OE pump.
Pressure comes up instantly with key on to 41 lbs.
And then, with key still on, pressure drops down to 19 lbs within 3 or 4 seconds. It takes about 10 mins more to slowly drop to 0 lbs.

Car runs good, with the exception of long crank times. More when engine is cold.

IIRC, pressure should hold for a lot longer that this?

Joel
Posted on: 2011/5/16 0:40
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

BillH Re: Fuel Pressure drops quickly
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



Offline
Yea definately. Sounds like a bad pump or check valve.
Posted on: 2011/5/16 1:31
_________________
Every man dies but not every man lives.
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
Yea, I'll just replace the pump soon. I knew my luck was about out since it's been almost a year since anything "broke".

Thanks for the reply
Joel
Posted on: 2011/5/16 2:37
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

Matatk Re: Fuel Pressure drops quickly
Webmaster
SW Chicago Burbs
22792 Posts
Member since:
2008/1/7 0:00



Offline
What Bill said. Other possibilities are the fuel injectors leaking or the FPR regulator leaking. There are FSM steps to narrow it down. Best way is to pinch the feed/return lines at the tank and see if pressure still bleeds down.

Photobucket

Photobucket

Photobucket

Photobucket


I also have a write up in the tech library for replacing the fuel pump.

Matthew
Posted on: 2011/5/16 13:02
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc.
1989 Corvette...RIP
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
Thanks for the info Mat! I have the FSM, was just too lazy yesterday to go thru all the steps to check for this problem. My injectors and pressure regulator are approx 2 yrears old. I know the plugs are dry and and no liquid fuel from regulator.
And, since I'm thinking this car has the original pump it's no big deal to just replace it.
Seems like most people are happy with the Racetronix kit #fpa-011?

Joel
Posted on: 2011/5/16 15:25
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

BillH Re: Fuel Pressure drops quickly
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



Offline
Joel, note that there's also an install kit if you need it.

http://www.racetronix.biz/customkititems.asp?kc=FPA-011&eq=
Posted on: 2011/5/16 15:58
_________________
Every man dies but not every man lives.
Transfer the post to other applications Transfer

hdfire Re: Fuel Pressure drops quickly
Guru Newb
Crest Hill, IL
48 Posts
Member since:
2010/12/19 17:22



Offline
Replaced my pump about 2 weeks ago with the racetronix parts. Much easier task than I anticipated. Still having some other issues, but the pump & install kit was top quality!
Posted on: 2011/5/16 17:10
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
Thanks Bill. That is the kit I would go with.
I thought Summit had these, but can't find it listed on the web site.

Joel
Posted on: 2011/5/16 17:17
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

BillH Re: Fuel Pressure drops quickly
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



Offline
Quote:

joeld wrote:
Thanks Bill. That is the kit I would go with.
I thought Summit had these, but can't find it listed on the web site.

Joel


Funny, I was in Summit today.
Nope, doesn't show up but they do have the AC Delco.
http://www.summitracing.com/parts/ACF-EP375/
Posted on: 2011/5/16 23:04
_________________
Every man dies but not every man lives.
Transfer the post to other applications Transfer

Matatk Re: Fuel Pressure drops quickly
Webmaster
SW Chicago Burbs
22792 Posts
Member since:
2008/1/7 0:00



Offline
When I calculated price, the racetronix was cheaper for a walbro pump/setup than the ac delco with sock and gasket even with gm "employee" price.

Joel - get the kit:

http://www.racetronix.biz/customkititems.asp?kc=FPA-011&eq=

Base Price: $ 109.00 Your Price: $ Quantity:
To take a printable version of this Kit Click here.
Item Name Price Qty

Fuel Pumps - In-Tank More Info

190/Hr Fuel Pump $ 1
Fuel Pump Installation Kits (RX-PIK) More Info

C469 1986-89 Fuel Pump Installation Kit $ 1
Select options; the kit price is automatically updated with the new price
Item Description

FPA-011 - 1986-1989 C4 Corvette Fuel Pump Assembly - Factory Upgrade 190LPH


* Walbro 190L/Hr Pump
* Filter sock - 30 micron filtering (factory=70 micron)
* High pressure fuel line
* Stainless gear clamps
* Rubber pump mount
* Pump sound insulation sleeve
* C4 fuel tank gasket
* Stainless hex-head tank bolts, washers and o-ring seals ( 9 pieces)
* Hex key
Posted on: 2011/5/17 1:18
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc.
1989 Corvette...RIP
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
One more question: I've seen a couple of posts with folks using a zip tie to secure the wires inside the tank. IIRC, Mat had this tip in his write-up. What kind of zip tie can withstand the gas? Most plastics I've dealt with in the past would dissolve in gas after a few hours.
I must be missing something here.

Thanks
Joel
Posted on: 2011/5/25 2:04
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

Matatk Re: Fuel Pressure drops quickly
Webmaster
SW Chicago Burbs
22792 Posts
Member since:
2008/1/7 0:00



Offline
I just used what I had laying around. I don't know how well it will withstand the gasoline. I'd say get the outdoor rated ones vs regular, they are stronger and more resistant to elements.

Matthew
Posted on: 2011/5/25 11:26
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc.
1989 Corvette...RIP
Transfer the post to other applications Transfer

BillH Re: Fuel Pressure drops quickly
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



Offline
Quote:

joeld wrote:
One more question: I've seen a couple of posts with folks using a zip tie to secure the wires inside the tank. IIRC, Mat had this tip in his write-up. What kind of zip tie can withstand the gas? Most plastics I've dealt with in the past would dissolve in gas after a few hours.
I must be missing something here.

Thanks
Joel


I had the connector come loose and shut down the pump (on the car in my avatar, watched the rest of the race sitting in the grass). Definately was zip tied after that.

Don't worry about the plastic, half the fuel tanks out there are plastic.

Get decent zip ties at HomeD, they used to carry T&B (Thomas & Betts). Just don't get zip ties from harbor Freight, they are real crap.
Posted on: 2011/5/25 13:31
_________________
Every man dies but not every man lives.
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
OK New pump is in, pressure holds better, but most of all the car now starts almost instantly! Always before there was a long crank time, been that way for 11 years. Feeling a little love for the car again.

Thanks
Joel
Posted on: 2011/5/25 23:56
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

larry00 Re: Fuel Pressure drops quickly
Guru Newb
4 Posts
Member since:
2010/2/6 12:23



Offline
Most all the new pumps are good but look out for the material used for the hose !
Cheap crap turns to mush in gasoline and since much of our stuff comes from overseas it's hard to tell apart from the good stuff.
It won't show up for a while then you hear the pump but get little or no fuel pressure !
If you can't tell the difference go to NAPA and buy the good stuff. Cheap insurance !
Posted on: 2011/5/31 15:19
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
Hi, I just installed the FPA-011 pump and C44 wiring assembly in my 89 corvette, I was having long start ups/cranking time also, now it just turns over and wont fire up...any thoughts why it wont fire up now?
Posted on: 2016/9/22 6:36
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
Check the fuel pressure with a gauge, should be 42 psi with key on engine off.

Joel
Posted on: 2016/9/22 13:56
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

BillH Re: Fuel Pressure drops quickly
The Stig Moderator
Reno
22702 Posts
Member since:
2007/12/25 0:00



Offline
Quote:

joeld wrote:
Check the fuel pressure with a gauge, should be 42 psi with key on engine off.

Joel


Yep, you have to start there, you need to know if there's pressure at the injector rail.
Posted on: 2016/9/22 14:44
_________________
Every man dies but not every man lives.
Transfer the post to other applications Transfer

bogus Re: Fuel Pressure drops quickly
Grand Imperial Pooh-Bah
San Pedro, CA
20856 Posts
Member since:
2005/9/7 0:00



Offline
Can you hear the pump fire up?

It should run for 2 seconds before the car starts to build pressure.
Posted on: 2016/9/22 17:44
_________________
The single biggest problem with communication is the illusion that it has taken place. - George Bernard Shaw

Education is the best tool to overcome irrational fear. - me

Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
no pressure at the rails, not even coming out of the tank , i can hear the pump but no fuel
Posted on: 2016/9/22 18:38
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
the pump seems to run for the 2 sec. but no fuel at the tank , pulled the line off at the tank turn key on pump made a sound , but no fuel.
Posted on: 2016/9/22 18:40
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
If you're sure pump is running, I'd say pull the pump back out. Possibly the pulsator slipped off or even the pump is loose from feed line.

Joel
Posted on: 2016/9/22 20:25
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
the pulsator is remove for this pump , and I check feed line , racetronix told me to check polarity so that's what im going to do now.....let you know if that works..
Posted on: 2016/9/22 20:33
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
Fyi polarity was wrong, car starts now.....still have the fuel pressure dropping fast...key on 45psi....20sec..drops to 15psi....2min. down to 0.....check pressure regulator its good...fuel injectors seem ok not getting a rich starting issue .....just the long crank time....what else im I missing?
Posted on: 2016/9/22 21:48
Transfer the post to other applications Transfer

joeld Re: Fuel Pressure drops quickly
Guru
Lawrenceville Ga
718 Posts
Member since:
2007/12/30 0:00



Offline
Glad it was a easy fix! I just assumed that kit was a plug-n-play.

The 1989 model year has a slight quirk in the "tune" that requires a longer crank time. Some info here:
http://www.corvetteforum.guru/modules ... id=192657#forumpost192657
Posted on: 2016/9/22 23:27
_________________
1989 Coupe,L98 automatic
Transfer the post to other applications Transfer

Matatk Re: Fuel Pressure drops quickly
Webmaster
SW Chicago Burbs
22792 Posts
Member since:
2008/1/7 0:00



Offline
My fuel pressure drops when off. I don't even worry about it. As for the long crank times, see the thread above. It's in the factory parameters for the 89.
Posted on: 2016/9/23 4:03
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc.
1989 Corvette...RIP
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
I assume it was plug and play also , sometimes its true about assuming LOL

thanks for your help and info.
Posted on: 2016/9/23 12:43
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
Where can I get a chip?
Posted on: 2016/9/23 12:51
Transfer the post to other applications Transfer

Matatk Re: Fuel Pressure drops quickly
Webmaster
SW Chicago Burbs
22792 Posts
Member since:
2008/1/7 0:00



Offline
Quote:

tomkatmn wrote:
Where can I get a chip?


Do you have any modifications to your car or is it stock? There are mail order companies, I currently use PCM of NC.

http://www.pcmofnc.com/product/1986-1 ... ette-mail-order-tuning-3/

Figure at least $160. You don't get any real power/performance gains from a chip. Most guys with a stock setup who want a chip do it to lower fan temps, eliminate VATS, etc. If you have modifications, that's where it's more important.
Posted on: 2016/9/23 13:59
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc.
1989 Corvette...RIP
Transfer the post to other applications Transfer

tomkatmn Re: Fuel Pressure drops quickly
Guru Newb
USA
9 Posts
Member since:
2016/9/22 6:17



Offline
im the 2nd owner the car only has 30k on it, I've done small mods to it , better air filter flow, other than that just stock.....if the chip helps with a lower crank time and or other improvements is all I need at this time. any advice I would appreciate. thanks
Posted on: 2016/9/23 18:06
Transfer the post to other applications Transfer

You can view topic.
You cannot start a new topic.
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.

[Advanced Search]


CorvetteForum.guru is independently owned and operated. This site is not associated with or financially supported by General Motors.

Copyright 2008-2015 CorvetteForum.guru

CorvetteForum.guru is a Guru Garage Site (Coming Soon!)

If you have any questions about our site, please contact us at Andy@corvetteforum.guru.

Powered by XOOPS 2.56 Copyright 2001-2014 www.xoops.org

Hosted by GoDaddy.com.