Fuel Pump Replacement How-To (56K beware)
Topic started by: Brocephus, Date: 12-02-2008 11:59 PM
Original thread: http://www.fiero.nl/forum/Forum9/HTML/000043.html


Brocephus (jarojj99@oneonta.edu) MSG #1, 12-02-2008 11:59 PM
      Ok, this is somewhat of a continuation thread that finishes telling the tale of how I fixed the problems I was experiencing with my stock '84 4-spd. But I decided to create a new thread so as to make it more compatible with the search function. Now, on with the show.


My engine was cutting out and missing badly. When under a load and the gas pedal on the floor, the rpms would flatten out at roughly 3000 and without careful manipulation of the throttle, it would go no higher. I changed all vacuum lines, tested all sensors, removed and thoroughly cleaned the intake manifold and changed the intake manifold gasket (it was sucking air). I changed the throttle body mounting gasket while I had it off to eliminate it as a source of vacuum leakage. I swapped the distributor for a known good one. I swapped out all sensors with known good ones. I reset the timing and double checked it countless times. I performed a compression test. I did a vacuum test. I tested the output of my alternator and verified battery voltage. Everything was in great condition but the engine ran like complete garbage. I even hired a priest, a rabbi and two voodoo masters and all I ended up with was a fondled Fiero with a kosher miss and a shrunken head. Nothing I did seemed to work and I was quickly becoming frustrated until I posted here and Frizlefrak reminded me to be a troubleshooter, not a trouble-guesser.....


 
quote
Originally posted by Frizlefrak:They need 3 things to run correctly;

1. Suitable compression
2. The correct mixture of fuel and air for a given engine speed and load.
3. A suitably strong spark delivered at the correct time.


The only test I hadn't done was a fuel pressure test. Reading my gauge with the key on/engine off, it was only 4.5 psi. Engine running, it was still less than 7 psi. These cars MUST have no less than 8-13 psi fuel pressure in order to run correctly. So my hat is off to Friz and the PFF crew and my a$$ is off to the parts house and The Man Palace.




sjmaye MSG #2, 12-03-2008 03:46 AM
      Nice post. Although deceptively simple your idea for marking the small lines to the tank is great. I took pics and struggled to make sure I had it right. I should have used your method.

Frizlefrak (dcarson@elp.rr.com) MSG #3, 12-03-2008 04:02 AM
      Well, if there was an Oscar for tech tips, this one would win it. Excellent write up Bro....ya did good.

Glad to hear all things are well again.

I forgot how rusty things get up north. If you saw the undercarriages of our Southern cars you would hate us.

OH....almost forgot....I love your master cut off switch on the battery. That just made it very close to the top of my to-do list.

[This message has been edited by Frizlefrak (edited 12-03-2008).]

Frizlefrak (dcarson@elp.rr.com) MSG #4, 12-03-2008 04:21 AM
      Oh.....before I forget, here's one tool you might add to your Man Palace next time you're out stimulating the economy....



I paid $45 for this bad boy at Harbor Freight Tools. It's a good soldier and has served me well. So far it has...

1. Helped drop three Fiero gas tanks (once on the same car twice in the same week....when yours truly neglected to replace the pulsator the first time)

2. installed a kitchen full of new cabinets during our last remodel. Makes installing wall cabinets a one man job.

3....oh, and it's even pulled a transmission once...imagine that.

So far, I've never had the good fortune to have a fuel pump fail with an empty tank. Bad karma or something....anyhow, the trans jack is a godsend. I've loaned it out twice, and both times had to beg to get it back. It has come in very handy, especially considering I'm only slightly better than 5 and a half feet and weigh a buck and a half dripping wet...and for some reason don't seem to be getting any stronger in my advanced age. Having a mechanical buddy doing the lifting is a big help.

I've never run out of uses for it.


Brocephus (jarojj99@oneonta.edu) MSG #5, 12-03-2008 08:19 AM
     
 
quote
Originally posted by Frizlefrak:

Well, if there was an Oscar for tech tips, this one would win it. Excellent write up Bro....ya did good.

Glad to hear all things are well again.

I forgot how rusty things get up north. If you saw the undercarriages of our Southern cars you would hate us.

OH....almost forgot....I love your master cut off switch on the battery. That just made it very close to the top of my to-do list.



Well Friz I thank you for the kind words and hope to provide another write up as soon as something else breaks.

I specifically searched for a car south of the mason/dixon line because it doesn't take a genius to figure out why the north is called "the rust belt". I won this car for $177.50, drove to Clarksville, TN to get it only to discover that they guy had just moved to TN from Michigan...


Take I-10 to 54.
Go north til you hit Cassidy.
Make a right and talk to the nice men with guns.

That's where I'm from, hehe. I spent 372 days in El Paso and I loved it as much as other hated it. On Fridays and Saturdays, I'd go to Graham's Country Dance Bar and sing karaoke but when I wanted a smaller crowd, I'd go to Incredibles over off of Alabama, just west of Willie Beaumont Hospital.

Well Friz, I need to go start my day and get some coffee. You take care and I'll talk at ya later.

[This message has been edited by Brocephus (edited 12-03-2008).]

Brocephus (jarojj99@oneonta.edu) MSG #6, 12-03-2008 08:34 AM
     
 
quote
Originally posted by sjmaye:

Nice post. Although deceptively simple your idea for marking the small lines to the tank is great. I took pics and struggled to make sure I had it right. I should have used your method.


You know, I'm not altogether sure how I came up with that idea, but it's been a huge help while doing my Nissan to Fiero swap. I had to mark all the wiring harness connectors like that because I can't speak Japanese, hehe.


ltlfrari (dave_ellis_@hotmail.com) MSG #7, 12-03-2008 08:51 AM
      Great write up, gotta love this picture:



Curlrup MSG #8, 12-03-2008 08:55 AM
      + for you very nice.

Frizlefrak (dcarson@elp.rr.com) MSG #9, 12-03-2008 02:09 PM
     
 
quote
Originally posted by Brocephus:

Take I-10 to 54.
Go north til you hit Cassidy.
Make a right and talk to the nice men with guns.

That's where I'm from, hehe. I spent 372 days in El Paso and I loved it as much as other hated it. On Fridays and Saturdays, I'd go to Graham's Country Dance Bar and sing karaoke but when I wanted a smaller crowd, I'd go to Incredibles over off of Alabama, just west of Willie Beaumont Hospital.

Well Friz, I need to go start my day and get some coffee. You take care and I'll talk at ya later.



Ever get over to Roscoes for a burger? I won't ask about Chicos, that much is a given....it's part of a GI's initiation package to Ft. Bliss. If you ever get back, stay on 54 to the Sun Valley exit, take the exit, and my humble abode is a stone's throw away. Be proud to sip a couple of cold beverages and swap lies with ya.



flimbob MSG #10, 12-03-2008 02:14 PM
      Great Post! I'll be doing this to fix the lying guage soon.

Larryh86GT MSG #11, 12-03-2008 02:35 PM
      Very nicely done. Educational and entertaining.

fieroboom (fieroboom@gmail.com) MSG #12, 12-03-2008 04:19 PM
      Superb writeup. I'd love to see a lot more of the awesome detailed how-to's crop up on here, so we can convince Cliff to make us a "How-Tos, Tips, and Tricks" forum.
+ for you, great job!



Brocephus (jarojj99@oneonta.edu) MSG #13, 12-03-2008 04:58 PM
     
 
quote
Originally posted by flimbob:

Great Post! I'll be doing this to fix the lying guage soon.



Yeah, wish like hell I had the time to do it when I was in there, but I need the car for a new job and didn't want to risk screwin' something up. Besides, my fuel gauge isn't really all that far off. And with a gas station close enough I could hit it with a rock, I rarely, if ever, put it away without a full tank.

The thanks I've been getting for this write-up is makin' me wanna do more of 'em. Too bad most mods cost money or I'd do it full time, hehe. Your appreciation is appreciated and "tanks" for the +'s.


fieroboom (fieroboom@gmail.com) MSG #14, 12-03-2008 05:12 PM
     
 
quote
Originally posted by Brocephus:
Yeah, wish like hell I had the time to do it when I was in there, but I need the car for a new job and didn't want to risk screwin' something up. Besides, my fuel gauge isn't really all that far off. And with a gas station close enough I could hit it with a rock, I rarely, if ever, put it away without a full tank.

The thanks I've been getting for this write-up is makin' me wanna do more of 'em. Too bad most mods cost money or I'd do it full time, hehe. Your appreciation is appreciated and "tanks" for the +'s.


I felt the same way about my door disassembly how-to. Made me wish I'd made more of them before I got the car completely torn apart!


kwagner MSG #15, 12-13-2008 12:27 PM
      Thanks for this how-to, it was just what I was looking for!

ForceFedFlesh (abc1578@optonline.net) MSG #16, 01-16-2009 06:15 AM
      guys make sure you clean the connecter AT the fuel pump if it looks the least bit crudsy. will save you the trouble of a non working fuel pump after all that work.




with that little bit of crud on there it may look like the connecter MIGHT still work....but it did NOT.


FFF


h.d.fire (mmaver@comcast.net) MSG #17, 03-20-2009 04:25 PM
      One of the best tech articles I've read! NICE JOB!! I'm changing the pump in my 87' this weekend!



Brocephus (jarojj99@oneonta.edu) MSG #18, 03-20-2009 04:46 PM
     
 
quote
Originally posted by h.d.fire:

One of the best tech articles I've read! NICE JOB!! I'm changing the pump in my 87' this weekend!




Well I'm glad you enjoyed it, hehe. Best of luck on the pump and make sure ya come back and let us know how it went!


1MohrFiero MSG #19, 12-24-2009 05:05 PM
      Back on top



tbone42 MSG #20, 11-18-2010 12:16 AM
      Bump.. because this is the best tech post I have ever seen.

OldsFiero (burginsauto@frontiernet.net) MSG #21, 11-18-2010 09:19 PM
      Good job Bro. I'm sure it will help lots of folks. I'm sure glad mine dosen't look like that underneath-guess that's we dont drive the ones we want to keep nice up here in the winter. I haven't seen ya much lately-hope all is well. BTW,if I see you drivin that nice T-top you got when the salt gets laided down,you could be talkin with a much higher voice.
Marc


Wam3 MSG #22, 03-30-2011 07:27 PM
      BUMP - I have to replace my pump :-(

Brocephus (jarojj99@oneonta.edu) MSG #23, 04-03-2011 10:59 AM
      Funny to think that this old how-to is still helpin' folks 3 years after I wrote it, haha! Information is so timeless....

ALJR (aljr@jgmanzi.com) MSG #24, 04-03-2011 03:09 PM
      Nother + for you!

I didn't fear this project, but seeing pictures and haveing some pointers will make my FP replacement go that much smoother...

Nice well-documented How-to!

EDIT to add:
I think the only thing I would have dun different, would be to empty the tank first; assuming you have at least some fuel pressure from the bad pump...

[This message has been edited by ALJR (edited 04-03-2011).]

HI-TECH (centralvalley606@yahoo.com) MSG #25, 04-09-2011 07:25 PM
      my pumps out... i printed this thread out and its gonna go into my own how to manual. awesome write up.

Frizlefrak (dcarson@elp.rr.com) MSG #26, 04-09-2011 11:36 PM
     
 
quote
Originally posted by Brocephus:

Funny to think that this old how-to is still helpin' folks 3 years after I wrote it, haha! Information is so timeless....


Yep....fondly remember this one


crashyoung (jeffcrashyoung@gmail.com) MSG #27, 05-18-2012 05:30 PM
     
 
quote
Originally posted by ltlfrari:

Great write up, gotta love this picture:





Michigan lounge wear...
I prefer mine in black tho, a little more formal...
You have documented this task very well, I have done it once, and it looks like I need to do it again, unless I can get the dry tank to flow again!


firejo24 MSG #28, 05-18-2012 11:19 PM
      If you’re not careful with the cigarette you might wind up with this!
All kidding aside, great post. Thanks!



Dennis LaGrua (dlagrua@comcast.net) MSG #29, 05-19-2012 10:55 AM
      Nice job on the write up and the procedure is correct. The only thing that I would insure is that the small hose that connects the fuel pump to the supply tube in the tank is certified as S.A.E. J30R10 submersible fuel injection hose. Standard J30R9 fuel injection hose will fail within a year. Other than that I would prefer to use fuel injection hose clamps. Those plastic pinch clamps may work but I feel safer with fuel injection hose clamps.



jameejamz (jameejamz@gmail.com) MSG #30, 06-02-2012 04:56 PM
      Wish I had known this forum was out there before I decided to drop my tank. Currently the tank is lying about, and I am dreading figuring out which fuel line goes where. Shouldn't be OVERLY difficult, but just enough pain to make my day unpleasant. And that Trans jack would have come in SO helpful!

Alex4mula (torres_a@hotmail.com) MSG #31, 06-02-2012 06:07 PM
      Nice write up. This is the type of contribution that deserves a + The FP replacement was one of the biggest thing I ever did in my car back around 1992-3. After paying $200 for a replacement job it failed after one month. So with no $$ I had to do it myself in an apartment parking lot. After doing about 4-5 by now I think the hardest part of all is just removing and re-installing all the upper hoses.

Ponnari MSG #32, 09-23-2014 09:07 PM
      After reading this great write up by "crashyoung" NOW I AM READY! It's been about 15 years since I have done this job and I wanted to make sure I wasn't remembering it being easier than it was.

Thanks Much "crashyoung"


Patrick (mnofony@yahoo.com) MSG #33, 09-23-2014 09:24 PM
     
 
quote
Originally posted by Ponnari:

After reading this great write up by "crashyoung" NOW I AM READY!


I'm sure crashyoung is a wonderful fella, but it's Brocephus who did this great write-up... one of the best ones ever presented here.


Lou and Blue (mrlduet@yahoo.com) MSG #34, 04-03-2015 10:08 AM
      I'm about to change my fuel ump to prepare for my 3800sc swap. I will be following this thread.
Thanks !



Detainabull (rboffenburg38@yahoo.com) MSG #35, 05-23-2015 09:52 PM
      I'll be replacing the fuel pump on my next few days off...find this thread very informative. Nice to know what your getting into and how to prepare for things like this. Great write up

fieroguy75 (petehiggins75@gmail.com) MSG #36, 07-20-2015 08:50 PM
      The tank on my 85 by is already out and the yutz who took it out didn't Mark anything,now whAt

fieroguy75 (petehiggins75@gmail.com) MSG #37, 07-20-2015 08:51 PM
      I have no clue where the lines go


Adjustso3 (adjustso3@yahoo.com) MSG #38, 07-21-2015 02:05 AM
      This was an awesome How-To. I will be doing a FP in the near future and assumed it wasn't going to be too difficult. Match marking the fuel lines is an awesome idea and totally eliminates the chance of mixing them up. Thanks for taking the time to do this write up.

CJB118 MSG #39, 07-02-2016 09:05 PM
      Excellent posting, just the right combo of tech, safety nags and humor. We did the FP and fuel filter today on the CJB, using this write up. THANK YOU and +1.



RWDPLZ MSG #40, 07-02-2016 09:13 PM
      I used this thread to help me replace the fuel pump on my 84 ~5 years ago, thanks!

Patrick (mnofony@yahoo.com) MSG #41, 11-22-2016 05:13 PM
     
This classic thread from a few years back absolutely deserves to be moved to FAQs & HowTos
I'll bring it to Cliff's attention.

 
quote
Originally posted by Cliff Pennock:

FAQs & HowTos (or F&H in short) is a section where I will move, ehm, FAQs and HowTos to.

If you have a suggestion for a thread to move here, please post them in the "Suggestions" thread.




lorennerol MSG #42, 01-22-2017 08:55 PM
      Pulled the tank on my 87 today to do this project.

1. THANK YOU. Extremely helpful, especially the pictures.
2. Before you start go get a siphon pump thing. It's six dollars, and the auto parts store is so close to you that the taste of gas in your mouth from twice trying to start a siphon the way your grandfather did will still be in your mouth when you get home. And hours later. Even the ten chocolate chip cookies I ate didn't erase it.
3. On my car, two of the rubber lines go under the car to metal tubes. One to the fuel filter, the other is the return, I presume. The third goes into what looks like wire loom and follows the wiring harness through the frame firewall. I presume this is the charcoal canister. This rubber hose was on top and was a BUGGER to get off the tank. Just getting to the clamp was difficult and then I had to tip the front end of the tank way down and work on prying the hose off from the top. Even then it was a PITA.
4. My fuel pump doesn't have a short rubber hose attaching it to the metal tube. It has some other intermediary widget thing (no clue what it does) that sits between the metal tube and the top of the fuel pump and attaches to both.
5. The electrical connections on the Bosch fuel pump I got doesn't match the connector on the wiring. It came with a sort of converter cable. I'm not fond of this as more connections makes for more possibilities of sparking.
6. I don't think the OP mentions it, but you'll need to remove the support brackets from the coolant lines that run adjacent to the tank so you can swing them out of the way to drop the tank. Maybe this is obvious, but still seems worth mentioning.


css9450 (css9450@liquid2k.com) MSG #43, 01-22-2017 09:18 PM
     
 
quote
Originally posted by lorennerol:


2. Before you start go get a siphon pump thing. It's six dollars, and the auto parts store is so close to you that the taste of gas in your mouth from twice trying to start a siphon the way your grandfather did will still be in your mouth when you get home. And hours later. Even the ten chocolate chip cookies I ate didn't erase it.
3. On my car, two of the rubber lines go under the car to metal tubes. One to the fuel filter, the other is the return, I presume. The third goes into what looks like wire loom and follows the wiring harness through the frame firewall. I presume this is the charcoal canister. This rubber hose was on top and was a BUGGER to get off the tank. Just getting to the clamp was difficult and then I had to tip the front end of the tank way down and work on prying the hose off from the top. Even then it was a PITA.
4. My fuel pump doesn't have a short rubber hose attaching it to the metal tube. It has some other intermediary widget thing (no clue what it does) that sits between the metal tube and the top of the fuel pump and attaches to both.


Last time I had to do this job, the tank was completely full. I have one of those Motive Products bleeder bottles; its like a plastic bottle with a pump handle to pressurize it. I used it to pressurize my tank and it let me siphon the vast majority of the gas out. Over eight gallons, at least. Worked like a charm.

Yeah, that uppermost line goes to the Evap canister. The OP's is a little different which is probably a 4-cyl. vs. V6 issue or maybe early models vs. late. Its hard to get the hose off of it when its hidden way up there on top.... Its hard enough to even SEE it! Worst part of the job in my opinion.

The plastic widget thing is the Pulasator. I re-installed mine but some people here have removed it and used hose in its place. I figured its there for a reason so I would keep it.



Dennis LaGrua (dlagrua@comcast.net) MSG #44, 01-23-2017 12:31 PM
     
 
quote
Originally posted by css9450:
The plastic widget thing is the Pulasator. I re-installed mine but some people here have removed it and used hose in its place. I figured its there for a reason so I would keep it.


The pulsator is only needed when you use a Gyrator style of pump. It supposed to reduce pump noise. If you use a turbine pump like the Bosch the pressure is not in pulses so it is not needed.



hcforde (hankforde@gmail.com) MSG #45, 04-13-2017 09:34 PM
      I am about to drop 2 tanks to replace the fuel pumps. Thanks, Great write up still so many years after.

Much appreciated!!!


1984_barn_find (sambunjan1969@gmail.com) MSG #46, 07-23-2017 11:16 PM
      Sooooo I need help..I have an original 1984 se and it had the original fuel pump... the replacement came with an entirely different connection (in fact I don't know how to take apart original.) so what do I do?

USMUCL MSG #47, 07-24-2017 07:35 AM
     
 
quote
Originally posted by 1984_barn_find:

Sooooo I need help..I have an original 1984 se and it had the original fuel pump... the replacement came with an entirely different connection (in fact I don't know how to take apart original.) so what do I do?


Are you talking about the pump itself, or did you buy a new sending unit from the Fiero Store?



NiotaFiero (geguffey@comcast.net) MSG #48, 08-09-2017 11:30 AM
      I sure wish there was a way for the pictures to show.