1987 1.9 GTI not starting. How to check fuel pump?

[Joecar 2 1 Cars]

Hello everyone,

first post on here, so I hope that I am not breaking any rules. 

 

I have bought a 1987 1.9 which has sat for around 10 years as a project car. Jokes on me - I have very little experience with cars, so I'll have to do a lot of learning by doing (which is why I am doing this - and because the 205 is awesome!). 

 

The car did start up fine(ish) when I picked it up - the seller started her up to drive her on the trailer. The seller reported that it might have a faulty fuel pump relay, though. After picking the car up I had to let her sit for a few weeks since winter got in the way and I can't use the garage. 

 

So naturally I changed the oil, the fuel filter and put some fresh fuel in and wanted to start her - with no luck. She cranks, but no start. Symptoms:

- Fuel pump relay is clicking. I do not know whether that means it is actually working, but it looks like it was replaced in the last 15 years or so. We tried to measure it through and are pretty certain that it is working, although not sure

- No noise from the fuel pump when cranking the engine as far as I could hear

- Fuel lines are still dry (from the fuel filter change)

- Fuel pump fuse gets very little voltage

 

We'd like to hook up the fuel pump directly to some sort of power supply to see whether it's the culprit or not. Do you have any tips for doing so, or any other things I should check first? The weird thing is mostly that the car did not have a lot of trouble starting when I picked it up.

 

Also, two more questions since I was not entirely sure: When cranking the engine, will it only fill the fuel filter or also lubricate the engine? Also, is the starter motor on the sturdy side and doesn't mind some repeated cranking?

Just trying to make sure I don't cause excessive wear.

 

Thanks in advance and I am looking forward to being a part of the forum! 

[DamirGTI 342]

10 years of no use/starting/driving , likely the fuel pump might be jammed up from (stale) fuel varnish ... especially if it was left standing all those years with old fuel still in the tank .

 

To test the fuel pump function , simply use an charged spare battery (or "power probe" if you have one) and connect the pump directly to it ... fold the rear seats and connect + and - from the battery with some jumper wires directly onto the fuel pump connector .. if it's good it'll start spinning and you'll hear it .

Also , check the fuel pump earth .. it's earthed on the body panel beneath/under the left rear lamp , sometimes the connection breaks or oxidizes and needs repairing or simply cleanup . 

 

 

While cranking it'll prime the fuel system and also lift the oil from the sump up trough the engine but not as much .. for proper oil distribution over the entire engine insides and building up oil pressure it needs to be started and running/idling for a few seconds .

If you don't go mad with continuous long cranking , the starter will be fine .

 

 

D

 

 

Edited January 25, 2021 by DamirGTI

[Joecar 2 1 Cars]

Hey Damir, thank you for the swift response! 
I only get to work on the car on the weekends, but I'll test the fuel pump next weekend and will report back. Here's to hoping it's the ground that needs some cleaning. 

 

-Josef 

[farmer 328 1 Cars]

I had a pump that spun under a spare battery but didn't have enough juice in it to fire the car up

 

I changed it after doing a few checks and it was fine with a spare unit attached 

Edited January 25, 2021 by farmer

[Joecar 2 1 Cars]

Hey guys, update. We hooked the fuel pump to a 12v source and it actually ran and managed to build up fuel pressure! 
 

We then measured the voltage that arrives at the fuel pump connector and it turned out to be only 5V. 
So, what does this tell me? Should I be investigating whether there’s a fault in the relay (unreliable solder joint, for example) or could this still be a grounding issue? 
 

On a wholly different note: I had the car sitting outside and now the rear seat carpets/floor is very wet (like, soaking...). Did any of you encounter this and can tell me what’s the reason? 
 

Best,

joe 

[DamirGTI 342]

'87 that's an Ph1 car right ?

 

Is that 5V measured with just ignition switched ON position , or while cranking ?

 

Does the starter spin as it should or is it a bit on a "slow side" ?

 

Could be the relay , it's in the engine bay under the battery on a Ph1 205 , pop off the plastic cover and inspect solder joints , resistors , diodes etc. with an magnifying glass . Check also each individual terminal inside the relay connector (smaller ones tend to break , rust , or push back in especially on Ph1 cars) .

 

Could be bad earth as well .. check with the multimeter , if in doubt remove rear left lamp and have a look at the earthing point on the bodywork .. it gets kinda damp on the rear side of the car thus not unusual for the wiring oxidation to occur there .

 

Check the battery is good (try another spare battery if in doubt) , and check battery clamps .. remove the clamps and clean up the + and - battery terminals with an piece of scotsh-brite pad , insides of the clamps also , tighten back the clamps so that they make good contact .

Also , from the battery -/neg. post follow the cable to the earthing point (usually gearbox , and later models inner wing as well) check and clean up the connection .

 

Water intrusion at the back is commonly bad/shrunken quarter window seals , you can buy new ones @ the Peugeot museum site :

https://www.pieces-de-rechange-classic.com/205/395-joint-vitre-de-custode.html

 

D

Edited January 29, 2021 by DamirGTI

[Joecar 2 1 Cars]

Hey Damir, thanks for the detailed response! 

The car is a Phase 1.5. So the relay is in the glove box, and it does klick (not sure whether that indicates that it's actually working).

The 5V is measured while cranking. The starter sounds fine, also I already put a new battery in since the old one was completely dead.

 

I'll check the earth today, iirc it's behind the rear left lamp for Phase 1.5 as well, right?

 

Thanks for all the info, also about the read window seals! Once I get the car actually running I'll get these. 

[Joecar 2 1 Cars]

Soo, I checked the earth connections and found them to look good enough. The earth behind the rear light looked dodgy so I took the whole thing apart (it had a clip with multiple earth cables running into it, which then went into some sort of adapter). Once the weather allows it I'll check it with the multimeter as well. 

 

I also took the relay apart. It's from "G. Cartier", I have never heard of that brand and could not find anything about them. It looks good in my opinion (see attached pictures), or does anything stick out to you guys? 

IMG_5896.HEIC

IMG_5897.HEIC

 

Edited January 30, 2021 by Joecar

[welshpug 1,661]

Cartier is one of the original brands of relays you will find on a 205.

 

 

are you getting a decent 12v to the relay?

 

your images are not working BTW.

Edited January 30, 2021 by welshpug

[Joecar 2 1 Cars]

Hey, good to know thanks. 

I've reuploaded the photos: https://imgur.com/a/FmqD8H6 - I really can't tell whether anything is wrong with it.

 

The relay itself gets 12v with no problems. However, connecting e.g. pins 30 and 87b (with a small cable with a fuse built in) does not do anything. Should I be checking all the ground connections more thoroughly or could it still be the relay that is causing trouble? 

[DamirGTI 342]

Do you have blown fuse No. 14 ? it's the last fuse from left to the right on the fuse box .

 

Do you have spark ? does the ignition works ? (as the relay needs pulse signal from the ignition..)

 

D

[DamirGTI 342]

6 hours ago, Joecar said:

However, connecting e.g. pins 30 and 87b (with a small cable with a fuse built in) does not do anything.

 

No wait ! try that again , need to connect pin 30 and 87 .. that should power up the fuel pump .

If wanted to start it like so then connect pin 30 + 87 + 87b .

 

D

[Joecar 2 1 Cars]

The fuse was fine, I still replaced it to make sure (which, sadly, didn't make a difference). I have spark as well. 

 

I'll try connecting the three pins once I'm able to work on the car again on Thursday or Friday. Thanks in advance, I hope she starts! 

[Joecar 2 1 Cars]

Hello everyone, today I cleaned up the grounding wires (did not do anything). 
However, I discovered something weird. 

At the ground harness in the trunk there were two loose cables. I was not sure where they belong, but when I plugged one in the Fuse #7 blew :/. Please see the attached pictures, can you guys help me out where these should belong? I’m not very good with wiring diagrams. 
 

All best,

Joe 

[DamirGTI 342]

Probably for the boot light , light blue live + and yellow/green earth - .

 

 

 

D

Edited February 5, 2021 by DamirGTI

[Joecar 2 1 Cars]

Okay, too bad - I was hoping it'd have to do with the fuel pump ground. Thanks for the info. 

The harness that is shown in the picture is the ground for the fuel pump, isn't it? Just making sure that I got the right one. 

 

Today we'll keep going on to try and diagnose whatever is wrong with the fuel pump/relay/wiring. I'll also see if I can find the earth points on the front near the grille since the front indicators are not working. Hopefully we'll make some progress.

[DamirGTI 342]

Yes that yellow connector will be where the fuel pump is earthed .

 

Those factory earth blocks tend to rust and fall apart , if you find any that are bad remove them and pile up all the earth wires into one wire ring terminal and fasten on clean a body ground (can apply some vaseline on top to prevent oxidation) .

 

D

[Joecar 2 1 Cars]

I've already checked it and it looked decent, I even took the terminal apart, cleaned it and everything. However, I did not check the yellow plug that goes into the terminal, so I'll do that when I get the chance. I'll let you guys know when I make some progress. Thanks for all the help.

[Joecar 2 1 Cars]

Sooo, I am incredibly busy right now and had little (read: no) time to work on the 205. That'll change mid-march though, luckily. However, there's still an update: 

Just to make sure, I swapped the fuel pump relay to a new one which did not help. 

But when we measured the voltages, something weird came up: There's only 10v going to the fuel pump relay. It's down to 5v when cranking. At least, all of those 5v arrive at the fuel pump it seems. 

 

So what does this mean? Still a ground issue I need to resolve? Is the lower voltage while cranking normal? 

[Joecar 2 1 Cars]

Today I checked the ground connection at the front of the car, near the radiator. That one is in really bad condition, also some of the cables are busted open so I will have to re-do these cables and the whole ground connector (it's pretty corroded and one pin broke when. pulled the plug off.

 

Any tips for sourcing a new terminal, plug and wire to re-do these ground connections?