perdued

So, I was driving from Nagano to Niigata in Japan on the highway, on a section of road that steadily gets higher and higher towards a mountain pass. There were few cars on the road and I have diplomatic plates (don't have to worry about police pulling me over), so I was cruising at between 160-180km/hr for a good half hour or more as we climbed up the slope. Just as we crested over the highest part of the road (the road narrows to one lane in this part so I was moving at a more normal speed), I felt a complete loss of engine power that was totally sudden. One minute everything fine, next minute, nothing.

Pulled over and had to call JAF (the equivalent of AAA or CAA), which towed me to the nearest rest stop, and then a couple of days later, I had someone come up from Tokyo to tow it back (wasn't cheap but better than relying on JAF to do it).

So, I've just got the diagnosis and it appears the fuel pump locked up on me. We'll replace it, along with the filter, and hope that does the trick.

But in the meantime, I have a few questions please:

1. Was the fuel pump lock caused by the particular mix of circumstances here? I read in another thread about the "vapor lock" phenomenon, and I think someone else mentioned high altitude and running the car at half throttle for a sustained period of time. Is there a link here?

2. If we replace the fuel pump and filter and I get myself into that same situation again (I doubt it, but just for the sake of argument), is the same thing likely to happen again?

3. Since I'm replacing the fuel pump and filter, is there any other work that anyone would suggest doing while we're at it?

BTW, the car is 1990 S4 with about 87,000km on it.

Oh, and you have to admit, the 928 looks good everywhere and anytime, even when getting a lift on the flatbed!!

Thanks in advance!!

P.S. We continued the trip with a Japanese rental car, and I was reminded about how much gas the 928 guzzles. I'd say the Japanese little car we rented probably used about 1/4 as much gas. But it was like driving an appliance down the road, so I'd still rather pay for the gas to power that he-man engine in this real car!!

Landseer

There may be dual pumps, one inside tank, one outside. And possible issues with connecting hose inside tank. Will try to find those references for you.

dogleg

i don't think the altitude caused this problem.just coincidence,id say the pump just packed in.common enough fault.i just replaced mine a few months ago.did it get noisy before you lost power.stunning looking car you have there,not too many in japan i would guess?

perdued

No, no noise at all before lost power. Just all of sudden.

There are I'd say about 4 928s that I see rolling around downtown Tokyo from time to time. Mostly they are S4s, but there is this one guy that I see now and again in a beautiful white GTS that looks like a NASA rocket ship.

I'll be moving back to Canada this summer (Ottawa) and will be bringing it with me.

jcorenman

Great looking car, even on a flat-bed!

As Landseer said, there is a common failure mode on cars with the second in-tank pump ('89 onward, I believe).

Louie's thread from 2006:
https://rennlist.com/forums/928-foru...fuel-pump.html

My experience in 2009:
https://rennlist.com/forums/928-foru...mp-upated.html

AO's Epic Rant in 2011:
https://rennlist.com/forums/928-foru...ight=tank+pump

The in-tank pump does serve a useful purpose, to feed fuel to the main pump and avoid any low-pressure cavitation on the intake side, whatever the reason. The problem is that the rubber coupling used to assemble the in-tank pump to the fitting is not happy with ethanol (or some other crap they put in fuel these days), and splits-- allowing the main pump to ingest whatever is floating around in the tank. Replacing that short coupling hose with anything else solves it, I just checked ours after 2+ years and it is fine.

dogleg

might even be just the fuel pump relay or its connection!did you ship it out in the first place?

perdued

Thanks very much for the links and the advice. This is really helpful. A mechanic is doing the work for me, so now is the time to send along some instructions. My conclusions from reading are:

- It would be a good idea to ask to have the in-tank pump checked as it has likely disintegrated.

- If so, best solution is to remove it and replace with strainer used on the cars that came without the in-tank pumps.

- Replace main fuel pump.

I continue to wonder about the altitude issue (some interesting posts by Jim - #54 & 59 in the last thread), but maybe it was just coincidence.

To respond to the question, I bought the car here in Japan. Have been having a blast with it over the past two years in Japan but not looking forward to Canadian winters and speed limits!

928 at last

And, check the threads.....there's one fuel pump that's designed to run without the in-tank assist. Greg Brown's post I believe.

928 at last

Mine quit without warning on the highway a couple of years ago. Standard failure mode - no warning - Bits from the in-tank hose jammed the main pump.

jcorenman

Yes, absolutely. If you replace the main pump, and if the in-tank pump has a split hose and you don't check it, then the main pump will jam again without warning.

The only caveat is that the in-tank pump (or the strainer) threads into an aluminum insert molded into the plastic tank, and if the threads are corroded then the insert can come un-stuck from the tank. If this happens then it needs to be repaired, or the tank replaced. It is a small chance, but does happen.

That is a good choice, and I would then replace the main pump with the '87-88 pump that was designed to work with the strainer. The other choice is to fix the in-tank pump by replacing the coupling hose, and stick with the later pump.

Yes, but first see if they can get the current pump working. Pull it out, connect some wires and dunk the intake end into a can of Marvel Mystery Oil or some other light oil that is less flammable than gasoline, and connect it to 12v (or higher) with reversed polarity. If it starts running then apply the correct polarity and run some clean oil through it, to thoroughly flush out out. Given the price of pumps this is certain worth a try.

If you do replace the pump, I would use the same part# if you keep the in-tank pump, or the earlier pump if you fit a strainer. The early (87-88) pump used with the strainer is 928.608.104.02 (Bosch # 0 580 464 045), and the later pump (89-95) used with the in-tank pump is 928.608.104.03 (Bosch # 0 580 464 057).

We chose to stick with the in-tank pump for that reason, we do see 10,000 foot mountain passes with summer temps on occasion (most recently Tioga in Yosemite, Teton in Wyoming). But any problem with altitude would be temporary, and would fix itself as soon as things cooled off a bit-- which apparently yours didn't do. So I think it was a coincidence, they do happen on occasion.

Just keep the diplomatic plates and you will be all set!

And pictures, we need pictures!!

perdued

Thanks so much! I have lots to go on now and will report back.

In response to the request for pictures, here are a few (I assume you meant of the car in its entirety as opposed to just the fuel pump). I've had a blast driving it in Japan and am sorry to have to leave.

dogleg

the black and white shot is stunning! seems to have a way of making the subject a little surreal.love it your car must have being imported into japan after it was new, otherwise it would have been right hand drive.perfect for you to take back home.are there any rhd 928s out there?

Arnoud

Picture perfect car, beautiful!

As I was curious as to what are the specification of the (early) 87-88 pumps versus the (later) 89-95 pumps, I did a quick search and from http://www.bosch.co.nz/content/langu...l_Pump_WEB.pdf on page 40 the following information can be found:

0 580 464 045 (early, 87-88 pumps): 400 KPA, 141 L/HR
0 580 464 057 (later, 89-95 pumps): 400 KPA, 147 L/HR

So the later pumps have a little bit higher flow rate.

By the way: I checked my original never replaced (as I have all the receipts since new) in-tank fuel pump during November 2011, and the same as what all other have reported here: broken hose. I took it out and replaced it with the standard strainer, one problem less to worry about.

LT Texan

Perdued, that is one pretty car.

I bet you have a great time with her travelling outside of the urban areas.

But I wouldn't love driving her in Tokyo.

I'm sure it's been brought up before, but I'd hate to be on the wrong end of the shaken bill to keep her on the road.

Good luck with the repair.

perdued

By way of update: the advice received on this forum was exactly correct! I asked the mechanic to pull the in-tank pump and sure enough, it was toast, which they concur led to the main pump ceasing up. They say they've managed to secure a new main pump and filter, but they seem to be having some trouble locating the appropriate strainer (we're tossing the in-tank pump). In any case, they're checking about the strainer. We are also going to replace the fuel hose that leads from the strainer to the main fuel pump.
I was not informed of the exact part number of the replacement pump. Many on this forum seem to be running the "044" pump. Why the preference for the 044 pump as a replacement? Should I be pushing for this? What will the consequences be if a later pump is fitted with the earlier strainer (assuming we can find one)?

Thanks again!