[salieri164]

Hi,

I was wondering if any suggestions about the problem I've just noticed on my 92 164S.
When engine is cold - it starts fine, but if I drive and leave the car sit for about two hours – it won't start after first try. Just keeps cranking until I try second time and then it starts.
Has anyone pin-point this issue or any ideas what it is? Thanks in advance!
Sasha

 

[ChazzyD]

Mine did that very same thing before I pulled the fuel pump and replaced the short hose there at the pump with Gates submersible fuel hose. It wouldn't hurt to go ahead and replace the pump while in there and the check valve. Also, clean out the filter basket that the pump is mounted in. The main thing is though that the short hose gets old and cracked internally, allowing the fuel pressure to leak down. If yours still has a cloth covered short hose, than it is original and will be very old by now and not provide a good seal with the hose fittings. Alfisto Steve even found a car that didn't have a check valve at all. He put one in it, which I'm sure helped the car a lot.
Charles

 

[spokeless]

curious about this..

My '93 L does this occasionally.

Does the motor run rough for 5 -> 20 seconds after it finally catches? The only explanation I'd heard was a leaky injector - but they were supposedly tested, and all passed. Not sure of the procedure used for that.

I guess I need to explore the fuel pump/short hose phenomenon.

 

[salieri164]

Interesting. I'll have to check the short hose. Actually replace it while in there.
The motor does not run rough after it finally catches. It runs bit uneven for about 20 sec when cold start.
Thanks

 

[Alfisto Steve]

Interesting. I'll have to check the short hose. Actually replace it while in there.
The motor does not run rough after it finally catches. It runs bit uneven for about 20 sec when cold start.
Thanks

I doubt you have a fuel pump hose issue if it starts fine cold.

You need to do a fuel pump pressure check to verify hose is good before you go to all the trouble to do a trunk dive and pump pull.

So next time it won't start hot try removing fuel pump relay (non-red stripe one) and jumper pin 30 pink wire terminal to pin 87 pink-white wire terminal in relay holder by ignition coil on top radiator support. Turn on key and hear pump run then try to start.

 

[salieri164]

Ok Steve, thanks. I'll try and report findings...
Sasha

 

[ChazzyD]

Mine started fine cold, but would take two tries when hot. Fuel under pressure is much less prone to "vapor lock." The trunk dive is not fun, but on a car this old, it's something that is due and really makes the 164 as reliable and powerful as it was when new. I would expect to have to do it again if I was to buy another one of these cars, first thing along with the timing belt and water pump. I had to do it to the 240 Volvo as well. Same issue on the 240, internal (it has an external big pump and internal small pump) fuel pump failure and short hose replacement. It has run like a champ ever since. It used to be a dog, and now can overtake and run up mtns. A buddies Porsche 944 was almost worthless before fuel pump replacement and new check valve. He went through all kinds of parts swapping until he put a fuel pressure gauge on it and discovered the fuel delivery issue. That stuff just gets old after 15 - 20 years. These Bosch fuel delivery systems are hardy and long lasting, but there comes a day when the car becomes problematic until that stuff gets zeroed out.
Charles

 

[salieri164]

Steve, after the same symptom today, I’ve jumped the terminals as you’ve mentioned. I could hear the pump running and afterwards engine started just fine. Does this rule out the fuel pump? Thanks for helping fellas!

I doubt you have a fuel pump hose issue if it starts fine cold.

You need to do a fuel pump pressure check to verify hose is good before you go to all the trouble to do a trunk dive and pump pull.

So next time it won't start hot try removing fuel pump relay (non-red stripe one) and jumper pin 30 pink wire terminal to pin 87 pink-white wire terminal in relay holder by ignition coil on top radiator support. Turn on key and hear pump run then try to start.

 

[salieri164]

Charles - that sounds like very healthy service to do regardless of anything. As of now, I just don’t want to start taking apart too many things since I’m planning on attending Tutto Italiano in August.
Frank – just to update my answer on your question, one interesting thing happened. While investigating this problem, I have cleaned the relay pins and terminals with electrical connection cleaner, dried with compressed air and protected with dielectric grease. After this, car started perfectly when cold and now I have smooth idle when cold. Still warm start issue but hopefully that’s next.
Cheers,
Sasha

Mine started fine cold, but would take two tries when hot. Fuel under pressure is much less prone to "vapor lock." The trunk dive is not fun, but on a car this old, it's something that is due and really makes the 164 as reliable and powerful as it was when new. I would expect to have to do it again if I was to buy another one of these cars, first thing along with the timing belt and water pump. I had to do it to the 240 Volvo as well. Same issue on the 240, internal (it has an external big pump and internal small pump) fuel pump failure and short hose replacement. It has run like a champ ever since. It used to be a dog, and now can overtake and run up mtns. A buddies Porsche 944 was almost worthless before fuel pump replacement and new check valve. He went through all kinds of parts swapping until he put a fuel pressure gauge on it and discovered the fuel delivery issue. That stuff just gets old after 15 - 20 years. These Bosch fuel delivery systems are hardy and long lasting, but there comes a day when the car becomes problematic until that stuff gets zeroed out.
Charles

 

[spokeless]

Frank – just to update my answer on your question, one interesting thing happened. While investigating this problem, I have cleaned the relay pins and terminals with electrical connection cleaner, dried with compressed air and protected with dielectric grease. After this, car started perfectly when cold and now I have smooth idle when cold. Still warm start issue but hopefully that’s next.

Sasha - Thanks for the follow up. I've only ever had intermittent hot start issues. When I get a cold start problem (as I have 3 times in 18 yrs.), it's always been the distributor cap - oil/cr*p contamination, moisture/cr*p contamination, or a worn down graphite central electrode. Each has occurred once.

The vapor lock is sounding right for my '93's symptoms (which reminds me.. Thanks, ChazzyD). The sweet spot for a rough hot restart seems to be a 20 min. delay after shutdown - ideal for heat soak. If the system is not quite maintaining adequate pressure, because of the short-hose/tank-pump/check-valve issue, I think this makes sense. If I wait two hours, I don't get the hard restart/rough-idling-for-20-secs. problem.

I predict a trunk dive is in my future - maybe with some fuel line pressure testing first, though..

 

[AlexGS]

As far as warm starts go, I've always found that holding the accelerator pedal slightly down helps, and my theory is that some of the injectors leak a small amount of fuel after the engine is switched off, effectively 'flooding' it or at least giving a less-than-optimal starting condition until more hours have passed and the excess fuel evaporated.

-Alex

 

[ChazzyD]

As far as warm starts go, I've always found that holding the accelerator pedal slightly down helps, and my theory is that some of the injectors leak a small amount of fuel after the engine is switched off, effectively 'flooding' it or at least giving a less-than-optimal starting condition until more hours have passed and the excess fuel evaporated.

-Alex

That is a distinct possibility as well, except the problem went away on my car after replacing the short hose in the tank and has not returned in the several years since.
Charles

 

[AlexGS]

That is a distinct possibility as well, except the problem went away on my car after replacing the short hose in the tank and has not returned in the several years since.
Charles

Also, I notice on re-reading that the time lapse Sasha describes (before a difficult restart) is longer than I've experienced. For the cause I was suggesting, it's generally difficult to restart within about half an hour, rather than two hours. So I agree with your diagnosis as well. It is of course possible to have more than one cause and a complex interplay of symptoms...

-Alex

 

[salieri164]

The problem disappeared. Strange. I am not sure what really caused the problem to go away, but I did clean some electrical components and fuel pump relay. Also I’ve noticed that during the time car wouldn’t start on the first attempt when engine was sitting warm for awhile, I was low on gas. Ever since, I kept the fuel tank at least half full with premium gas. Used premium before but this time changed the gas station. I’ll keep an eye on it to see if intermittent problem and if anything, I will certainly let everyone know. Thanks for such valuable advices!
Cheers

 

[ChazzyD]

Not running it low and the problem going away, supports the short hose theory. IMHO. Why? Because the short hose is likely always submerged and less likely to ever suck air.
Charles

 

[salieri164]

Charles, this theory also crossed my mind and by some means I agree with you. But on the other hand....if hose is bad, does it suck the air or under pressure releasing the vapor? What is the pressure inside the hose? I almost don’t believe that external pressure of the tank (amount of fuel inside) can hold higher psi of the hose, if that’s the case.
Time for ice cream on the other side of the city to get me low on fuel again and see what happens...

 

[goats]

why not take a simple measurement?

of fuel pressure, when starting, when running, and when sitting for a few hours or overnight, and then have some data to work with?

 

[salieri164]

Yes, I will do testing as well. I found your recommended steps (copied below), any other consideration when testing?
Thanks

“4. Check your fuel pressure and fuel flow. Easy to do -- for pressure, Tee in a gauge on the pass side fuel rail and start the engine -- we want about 42-46 psi. Turn engine off, and see if fuel pressure holds. ...”

 

[goats]

nope its easy

tee in the gauge, and take pressure readings when starting the engine, then while running, and then shut the engine off. Wait about an hour. See what the pressure is then. Its OK to drop a little over an hour but still should be well above 30 PSI.

Don;t bother doing a flow test until you verify good fuel pressure number.

 

[salieri164]

I finally found some time to work on Alfa....hhm more like spend some time in the trunk which was creepy & hilarious!
So my fuel pressure was just above 40psi but I was losing about 10 after 1 hour of sitting. So first thing I did I pulled the carpets from the trunk and check the visible vapor hoses and I am sure I did hear hissing sound from one of the 90deg 3/8” hose (as Charles mentioned on this link: http://www.alfabb.com/bb/forums/164-168-1991-1995/170120-1991-164s-gasoline-smell.html ) . This explained the gas smell after 30 min of driving.

While there (in the trunk) I’ve decided to try pulling the fuel pump without tank dive in order to replace the infamous short hose and inspect other components.
Cut the fuel by pulling the fuel pump relay while car is running until engine died, disconnected the battery and went digging for pump. It took me about half an hour to get screws out. Considering sitting in the trunk and being in some weird yoga position – it wasn’t fun!
Just out of curiosity, I’ve tried to replace the short hose without pulling the entire pump out. Bit tricky but I did it. Then after about 15 minutes of finding the right angle since strange inside shape of the tank, I was able to pull the whole fuel pump assembly out (see my funky hand sketch below for obstacles in yellow).
I was expecting much dirtier filter but overall condition was very good, but still I’ve replaced all the rubber. Just FYI - I’ve found submersible fuel line (5/16” SAE30R10 by Gates) in local Napa store. Also to mention...while pulling the pump out, I accidentally disconnected the ‘soda straw’ but luckily ended up in my hand. Thanks to you guys & your postings about the soda straw, I was able to find upon assembling and actually see one of 8 holes where this straw belongs.

One thing I would like to point out is cleaning (to some degree) the fuel tank inside. This is dangerous step (just like the whole project) since you are exposed to open tank and fuel fumes! So unless you know what you are doing – I’d highly recommend you DON’T do this whole project. With fuel tank empty, I was outside, with no source of any electrical components that may spark the fire and I used the Sun as my natural light source.
From the hole on top of the tank, I was able to see inside the tank. I’ve used small hose connected to siphon suction pump (anyone guess what kind of pump is this- shown on image?), in order to ‘blow/push’ all the dirt into one most visible corner. Then I’ve sucked that collected crap out with the pump as much as I could. The rest, I used the magnetic extension tool/screwdriver for pickup metal shavings. Took me about 4 pickups and each time I’ve had this much (see image below) of deposits picked up.

Placing the fuel pump assembly back into the tank was again bit tricky since the angle issue mentioned earlier and as shown on a hand sketch. After job was done, started the car with no problems, check the pressure and it was holding steady with slight drop after awhile. No more problems starting the engine when warm!

Thanks for help!
Cheers,
Sasha