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Posted by: johnpierre Jun 23 2020, 10:25 AM

hello 914 community

so I was driving the other Sunday - nice drive with no traffic due to covid, doing 80 on the 405 heading south, for those of you that don't live in LA, that is in LA ;-) and then all of a sudden I just lost power.

it sounded like I ran out of gas but that of course is impossible as the tank was 1/2 full. I have a 73, 1.7 fuel injected engine and I have never had this issue.

I suppose I can tow the car to a garage but I thought I might put this out there in case this sounds familiar to anyone and I could try to troubleshoot the issue first. is there anything I can check rather easily to solve this? has this happened to anyone else under these conditions?

I looked all around the top of the engine as best I could when it happened and I didn't see anything disconcerted or otherwise out of place - but then again I don't really know what I was looking for and it was hot so I really could feel around that much.

-jp-

Posted by: BeatNavy Jun 23 2020, 10:30 AM

When you cycle the key to "on" position do you hear the fuel pump priming (for roughly 1.5 seconds)?

Could be fuel or it could be spark, but that fuel pump test is the easiest (you do it every time you start your car).

Posted by: DRPHIL914 Jun 23 2020, 10:37 AM

,most likely pump issue, relay or just loose wire on coil , ground etc

Posted by: ndfrigi Jun 23 2020, 10:44 AM

Do you have pertronix on ur dizzy? if yes try to replace it with standard points and also like Rob and Dr. Phil said, check your fuel pump and if there is a loose wire from coil.

Hopefully it is just minor issue and you can drive the car again especially time to enjoy the 914 this summer.

Posted by: fiacra Jun 23 2020, 11:00 AM

Despite what the gauge says did you check the tank to make sure there is fuel in there?

Posted by: Frankvw Jun 23 2020, 11:06 AM

if the spark is OK...Check fuel (as mentioned), if you have fuel in the tank, could also dirty or clogged up fuel filter/filtersock. troubleshooting starts ! good luck.

Posted by: jd74914 Jun 23 2020, 11:52 AM

I had this happen and it turned out my 3 port fuel pump was bypassing from pressure to return (regulator spring failed). Not sure how common this is, but same symptoms you had.

Posted by: KELTY360 Jun 23 2020, 02:56 PM

Fuel pump relay on the relay board.

I've had the same thing happen in two different 914s and diagnosed it in a couple of others. Easy fix; just swap in one of your headlight relays and see if it works. Good Luck.

Posted by: GregAmy Jun 23 2020, 07:40 PM

Similar experience to the above: verify solid terminals between the 12- and 14-plug terminals and the relay plate. Remove, clean, ever-so-slightly spread the quartered mail terminals...


(I hesitate to add "use dielectric grease" because you should, as writing that always causes incorrect counter-arguments here...but use dieletric grease.)

Posted by: johnpierre Jun 23 2020, 09:40 PM

hey there - thanks for all the help

here is what i found based on your help.

#1 im pretty sure the fuel pump is priming - i can here the low whine when i turn the key

#2 checked all the fuses and they all look old but non blown, i turned each fuse to see it that would make a better connection

#3 it looks like im missing a fuse on either end - not sure i even know it they where there to begin with

$3 looked at the coil and it all seemed to be connected, no lose wires

#4 i did find a vacuum hose that is not connected, i can't seem to figure out where the hell it connects to however it is coming from a long black straight tube that is at the front of the engine bay

#5 checked tank to make sure there was fuel - there is

#6 there are only 10 fuses and i could not see any numbers anywhere - must be on the plastic cover that departed me some time ago so i don't know where fuse controls the pump

here are some pics to see if you can see something i did not


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Posted by: johnpierre Jun 23 2020, 09:41 PM

the coil presumably...


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Posted by: johnpierre Jun 23 2020, 09:42 PM

vacuum hose to nowhere


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Posted by: johnpierre Jun 23 2020, 09:43 PM

this is where the vac hose begins


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Posted by: johnpierre Jun 23 2020, 10:01 PM

so going with a faulty fuel pump - where is it located ? can i just buy one from pelican or AA and pop it in?

Posted by: KELTY360 Jun 23 2020, 10:17 PM

Forget about the fuses. It's the fuel pump RELAY. Located on the relay board on the driver's side at the front of engine bay. Take off the plastic cover and you'll see round relays, a couple of fuses and a harness connector. The round relays are the same as the headlight relays on the motors in your frunk. Do a search. 99% sure it's your problem and easy to fix. Always carry spare relays.

Posted by: johnpierre Jun 23 2020, 10:23 PM

great will follow your directions in the morn when it is light out...

Posted by: 914_7T3 Jun 23 2020, 10:53 PM

Here are the fuse locations for a '73 from the owners manual. Looks like you are missing the left high beams (white 8 amp) and headlight motors (blue 25 amp)



As for fuel pump relay, you can reference this relay board diagram showing the underside to help identify the loacation.

Posted by: 914_7T3 Jun 23 2020, 10:53 PM

The dreaded double post!

Posted by: ndfrigi Jun 24 2020, 01:28 AM

that is the line for charcoal canister and not really affect the issue you are having now.

Posted by: GregAmy Jun 24 2020, 09:56 AM

Given:

...then I can't see how this has anything to do with the fuel pump electrical circuit.

Did I miss it or have you tested fuel pressure?

Posted by: johnpierre Jun 24 2020, 12:31 PM

ok here is the update:

found the relay board - thanks for that - inspected the little fuses and they were ok. nothing looks burnt or damaged so i removed the two round fuses from the light motors and swaped out two from the relay board to see if that would solve the issue, it did not.

i have ordered three new round fuses from Pelican here in long beach, they will arrive tomorrow and i will install them and see what happens.

here is a curious thing however:

now i don't here the low whine of the fuel pump anymore and while i was trying to start the car i heard a pop and saw some smoke coming from the engine bay, i looked all over and could not see anything burnt, or still smoking. i could not smell anything buring so just assumed it came fromthe tail pipe area.

Posted by: mrholland2 Jun 24 2020, 04:42 PM

Are you sure everything is okay in the distributor/plugs/plug wires/coil arena?

Posted by: johnpierre Jun 25 2020, 08:26 PM

so here is the update:

fuses arrived from pelican, i replaced all three of the ones on the relay board - nothing has changed - still sounds like it is not getting any fuel.

however i can again hear the low whining sound that i am assuming is the pump - also looked all over the coil distrubutor cap area and it all looks ok

here are some pics

what is the next thing to check or trouble shoot???

Posted by: johnpierre Jun 25 2020, 08:28 PM

old relays


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Posted by: johnpierre Jun 25 2020, 08:29 PM

relay board with new relays installed


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Posted by: johnpierre Jun 25 2020, 08:31 PM

coil / distributor cap area - looks to be ok right ???


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Posted by: type2man Jun 25 2020, 08:48 PM

Remove the intake and pour fuel into the throttle body, if it starts, then you have a fuel delivery problem

Posted by: johnpierre Jun 25 2020, 08:53 PM

copy that...

Posted by: johnpierre Jun 26 2020, 11:41 AM

is the throttle body right under the air filter ?

Posted by: rjames Jun 26 2020, 03:10 PM

This is concerning. I would check the all of the wiring in the engine bay very closely, making sure everything is connected correctly and there's no broken or exposed wires shorting something out.

Something else to check- take the distributor cap off and make sure the small braided ground wire inside is still attached. The car won't start if it's not attached or has a bad connection.
Once upon a time I wired my distributor up incorrectly and fried the ground wire. A bit of smoke and a toasted ground wire was the result, as was a car that wouldn't start anymore.

Posted by: johnpierre Jun 26 2020, 07:47 PM

ok will do

Posted by: euro911 Aug 16 2020, 11:38 AM

Did you get the issue figured out yet?

Posted by: rhodyguy Aug 16 2020, 01:54 PM

Do you have spark? Easy way is hook up a timing light to a plug wire, any one of them will do. Then engage the starter. You're only looking for spark. Not timing. Yet.

Posted by: mankowski Aug 17 2020, 07:33 PM

Intermittent loss of voltage to fuel pump could be a bad relay board trace. That alone doesn't appear to explain what's going on here, but it might be contributing.

Posted by: johnpierre Oct 28 2020, 10:27 AM

bump...

Posted by: johnpierre Oct 28 2020, 10:38 AM

ok everyone - it as been a few months - i just been so busy i have not been able to really dig in on this issue.

i still cant start the car, $@!#%&

i replace all the round relay's that were on the board in the back engine bay, as recommended and still no luck

any suggestions as to what to troubleshoot next ??

i have a few open days that i can dedicate to this issue - i need to get this car running - the weather is changing here in LA and this is my favorite time to drive it. plus it is currently parked on the street (covered) and due to covid culver city stopped writing tickets for street cleaing but that is about to end so i need to be able to park the car in the driveway on the street cleaning days.

i suppose i could tow it to a shop but it just seems to me that it is a simple fix which i can perform myself but i just don't know exactly what to look at or test.

914 community what is the next step????

-jp-

Posted by: GregAmy Oct 28 2020, 11:04 AM

I'm still not clear if your pump is consistently running and you have fuel pressure? Have you tried jumping the fuel pump relay?

I'll reiterate that sudden stoppage on the highway is commonly related to electrical/wiring issues with the relay plate, its connectors, and terminals.

Posted by: euro911 Oct 28 2020, 12:54 PM

JP, there's also a couple of fuses next to each other on the relay board in the engine bay.

The 25 amp fuse (in the socket towards the rear of the car) is the main power fuse for the board - it protects the fuel pump and the heater blower fan.

The 8 amp fuse is only for a rear window defogger (if vehicle is so equipped).





If not already posted in this thread, go over Jeff Bowlsby's checklist: https://bowlsby.net/914/Classic/zTN_FI_FPChecklist2.pdf

Posted by: euro911 Oct 28 2020, 01:16 PM

Posted by: JamesM Oct 28 2020, 02:14 PM

on all counts.

Rather than guessing and replacing random parts in the hopes that the problem goes away though you need to actually diagnose what isnt working and then address that system.

Absolutely would look at the fuel system. As previously stated issues with the relay/relay board are super common (I have had them with every 914 I have ever owned and that is a pretty large number at this point) however because its usually easier to check for spark do that first just to rule it out.

So
Step 1: hook up a timing light, crank the engine. Is it lighting up?
No = Figure out why you dont have spark.
Yes = Look at the fuel system next.


Step 2: Do you have fuel pressure? Not hearing the pump at all is usually a give away that you dont, but hearing the pump run is not always an indicator that you do.
Get a fuel pressure gauge and throw it on the fuel rail!

No pressure + pump not running = something wrong with the pump or the electrical circuit/relay/relay board.

No pressure + pump running = bad pump or obstruction in the fuel line

Proper 29 PSI at the fuel rail when key is cycled/cranking = something other than the fuel pump system itself, start looking at d-jet Head temp sensor, MPS, etc (this is a d-jet car right?)

Whatever you do stop guessing though. Its pretty easy to test what is and is not actually working on these cars. Once you have isolated where the failure is you can stop randomly replacing parts.

Posted by: Tdskip Oct 28 2020, 02:29 PM

+1000

You need a definitive answer on if you are getting spark and fuel.

Autozone has spark testers for under $10. Buy one and report back, we can take it from there.

Posted by: jim_hoyland Oct 28 2020, 02:33 PM

If a fuel pressure gauge is installed in-line, fuel pump problems are easier to analyze.
If engine quits and the fuel pressure goes to zero, it’s fuel pump or it’s wiring
If engine quits and fuel pressure is say 2&, it’s not fuel pump; move on to ignition
Big question for you is: whether gas is being pumped. I would disconnect the fuel line in the engine compartment and turn the key. No gas, maybe kinked fuel hose or clogged filter; and, don’t forget there is a mesh screen sock inside your fuel tank.
Hopefully, you see gas

Posted by: euro911 Oct 28 2020, 04:20 PM

I sent JP a PM, offering to run up there to help diagnose the issue(s) ... waiting to see if/when it'd be a good day/time to do it

"Just give me some advance notice - and think about posting a 'Tech Day' on World to see if a maybe a couple of other local members could join in to brainstorm the issue(s).

I have compression tester, a leak-down tester, tach/dwell meter, timing light, floor jack & stands, etc., all ready to go ... (have wrench, will travel) "

If JP's OK with that, are there a couple of other 'locals' available to come give a hand, if he puts out a casting call?

Posted by: Tdskip Oct 28 2020, 06:24 PM

I might be able to help over the weekend (if extra help is needed)

Posted by: trick-e Oct 28 2020, 09:14 PM

I didn’t read all of the responses, but I’m just solving a similar issue.
Mine progressively got a little harder to start, and sometimes it wouldn’t. Now, it won’t start at all.

Confirm the pump runs when turning the key. If it does spray starter fluid into the throttle body to confirm it tries to start. If it tries, change the fuel filter first.
Next, Remove the fuel sender and/or expansion tank.
Shine a flash light into the tank.

How does the strainer look? Mine looked like someone had sealed the tank with that little mesh strainer in place. It was only a matter of time.
I’ll be pulling the tank and putting in a new strainer.

Posted by: johnpierre Dec 7 2020, 01:34 PM

ok so here is the latest with my drama:

#1 as I stated I replace the fuel relay, didn't solve the issue

#2 a friend of mine helped me replace the fuel pump in my 2001 chevy - took him all of 2 hours to drop the tank and swap out the pump and put it all back together. since he was so proficient at that I reasoned why not get him to trouble shoot the 914. this is what we found.

for sure it is getting spark - btw I purchased some new plugs and I also purchased a new battery - figured it could not hurt.

so now that the relay not the issue I am guessing the next thing to eliminate is the fuel pump? right?

I guess I should just order one from pelican and get it in there with a new filter and at the very least I have a new fuel pump - not that expensive of a part.

if the car starts I know that was issue and if not then I can move on to another part of the chain.

what are your thoughts ??? maybe I just check the fuel filter fist - see if it is clogged ???

-jp-

gotta get this baby running - the weather is perfect to drive it now....

Posted by: johnpierre Dec 7 2020, 01:36 PM

Posted by: rjames Dec 7 2020, 01:42 PM

Replacing the fuel pump might fix it, and then it again it might not.
Have you checked the fuel pressure yet as others have already suggested?

Posted by: rhodyguy Dec 7 2020, 01:52 PM

Was the tank sock examined? Partially fouled, they can suck flat under vacuum. = no fuel. No pump vacuum the sock releases and fuel might flow. For a while. Only takes a couple of minutes when the tank is out to r&r. Note the direction the supply spigot is pointing. If the pump is not the problem, swapping it out is a waste time and money.

Posted by: johnpierre Dec 7 2020, 02:28 PM

so I just checked with my friend and he said when I was turning the key there was fuel pressure and he could tell fuel was in the rails

so I guess it is not the fuel pump

is there an ECU on this car - the reason I asked is there is a box behind the batter that looks like a electridle unit - could the problem be in there ???

Posted by: GregAmy Dec 7 2020, 02:30 PM

Yup.

And before I bought a fuel pump, I'd ensure thre was 12V going to it. My wager is still on a problem with the electrical connectors/pins to the relay plate. I noted before what I did to resolve the same issue...

http://www.914world.com/bbs2/index.php?s=&showtopic=175444&view=findpost&p=2538175

Posted by: 914Toy Dec 7 2020, 02:41 PM

How did your friend know there "was fuel pressure and he could tell there was fuel in the rails"?

Posted by: sixnotfour Dec 7 2020, 02:48 PM

Has your pump been updated or still have the 3 port in the back ?

Posted by: rjames Dec 7 2020, 02:58 PM

Checking for fuel in the fuel rails isn't the same as checking the fuel pressure. To rule out the pump or the fuel pressure regulator you need to know what the fuel pressure actually is.

Posted by: euro911 Dec 7 2020, 04:28 PM

JP, You can pick up a fairly inexpensive fuel pressure gauge at AutoZone or Pep Boys.

Also pick up a couple of small hose clamps and insert it permanently inline in the supply line - somewhere you can see it in the engine bay


https://www.autozone.com/test-scan-and-specialty-tools/fuel-pressure-tester/innova-fuel-injection-pressure-tester/273356_0_0

Posted by: 76-914 Dec 7 2020, 05:37 PM

https://members.rennlist.com/pbanders/FPChecklist_frame.htm

Posted by: johnpierre Dec 9 2020, 12:06 PM

hey there

thank you for the link but I can't seem to open it
-jp-

Posted by: euro911 Dec 9 2020, 12:47 PM

Try this link, JP ... https://members.rennlist.com/pbanders/#Details

Scroll down to the D-Jetronic links

Posted by: jim_hoyland Dec 9 2020, 07:17 PM

And, I had this happen, the fuel pump ground must be secure. A loose or poorly crimped ground will stop that pump.
Common on ‘75s where there’s a chassis spade for the ground.