Hello. in the last few months we have been experiencing an intermittent problem of difficult starts on my wife's '93 945. It is a normally aspirated 940 with a Regina ignition and a single fuel pump (correct me if this is not the case on Regina cars). The symptoms are this. First start in the morning the engine cranks and cranks without starting. Then after a few separate attempts if finally catches and starts and runs fine if a little rough. Then after that for the rest of the day it will start quickly and run smoothly. Sometimes the car starts fine in morning, but still runs a bit rough for a few minutes, then all is well. This has been going on for several months and with approaching winter I am a bit worried of getting stranded. Is this a sign of dying fuel pump? Maybe something else? Please advise. I am all ears. This is wife's daily driver and she depends on it. I also get lumber with it on occasion. It's a great car and I love owning it. I hope I can make it run for another 200K miles. With help of people on this forum it may just be possible.

TIA!

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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

Check the fuel pressure regulator. My 940 was get progressively harder to start and the fault turned out to be the fuel pressure regulator.

There are two checks you can perform:

1.With the engine off, remove the return hose, on the back of the regulator (attached with a hose clamp.) Attach a length of hose the the return line and direct into a gas can. Start the engine and you should have a strong stream of fuel into the gas can. If the stream is weak you either have a bad regulator or bad fuel pump.


2. Pull the vacuum tube off of the regulator, if you see and gas on the vacuum side of the regulator then it needs to be replaced.

My regina fuel pump failed at 185,000 miles.

you can start the car and stick an approximately 3/4" dia tube down into the gas tank and listen. A failing fuel pump isnt hard to pick out (wasnt for me at least, it sounded for lack of a better term like it was 'shorting out')

The temp sensor would be good to check too... as others suggested.
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'90 245 224k, '93 945 184k

Is there a chance you have a flaky temperature sensor?

Ron
93 245

Is this an air temperature sensor? What does it have to do with starting? As I said, the car starts fine, only not always on the first try first time in the morning. Every other start is fast and smooth.

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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

There is a temperature sensor in the block under the intake manifold. On my 740 it was between cylinders 2 and 3 I believe. When working properly its signal tells the ECU that it is cold and extra fuel needs to be injected - kind of like a choke. If the wiring is flaky, as it was in my 87, sometimes it will work , sometimes not.

Ron 93 245

Where is the temperature sensor and how do I check it?

Thanks.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

Check the FAQ... I believe its located under the intake runners. Or I think you can check the resistance at the main ECU connector near the front passangers right foot.
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'90 245 224k, '93 945 184k

I've had pumps go in my Regina cars and replaced them. Your symptoms don't sound like a pump problem to me. But the suggestions to listen for the relay and pump by turning the key to position II and checking the fuel pressure at startup are good ones.

My first thought would be your Crank Position Sensor. If it is original, the insulation and so the wiring may have deteriorated. This is sometimes visually obvious, but try this test. When the car won't start, go out and wiggle the wire for the CPS (even better if you can do it while someone else is cranking). If manipulating the wire seems to change the situation one way or the other, than it's a pretty good sign you need to replace it.

How do I check the CPS? Where is it? If it were the CPS I would think the problem would not be limited to the first start of the day. This problem is strictly first start of the day. Then the car will start every time and quickly. Still, I would rather change the CPS than the pump, as I imagine it is both cheaper and easier to do.

Thanks.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

Get thee to the 700/900 FAQ under "select shortcut" at the top right of this page. Have a look at the section on engine sensors to learn all about the CPS, engine temp sensor, etc, etc.

I had symptoms just like yours on one of my Regina wagons and the problem turned out to be a bad CPS. When cold, the car might start right up. Or it might start after a lot of cranking. Or it might not start at all, but start an hour later. Car never quit once going. Tried a lot of things, but changing the CPS cured it. I knew it would be once I found that playing with the wire to the CPS would usually start it when it didn't want to. No HOT start is a more classic sign of a bad CPS, and I can't explain why mine wouldn't when cold or why worked sometimes, but that was the fix.

Thanks for the reference to the FAQ. I have read through the CPS section and through the temp sensor section and that made me more convinced that the problem is NOT either one of those. CPS failure is hot running related and the temp sensor richens the mixture when bad. Both seem to occur at fully warm states. My problem is: a) intermittent, b) NEVER on warm engine and c) ALWAYS on the first start of the day as in the pump lost its prime and needs extra cranking to build it up. The rough running at first may also be related to the loss of prime and presence of air bubbles in the system. Sound crazy? What of that check valve the pump has? I may already have a replacement pump (I own the car since 150K and the previous owner was very good about maintaining it). Any idea on the pump's check valve? How to check, whether or not my pump is original and has such a valve or it is replacement and lacks the valve?


Thanks!

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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

Those FAQ symptom descriptions aren't always 100% gospel, so CPS problems won't always be an exact match with a single cited description.

I wouldn't sweat the pump check valve either. In fact I'm not even sure the Regina pump has one. The main purpose for the Bosch pump check valve is/was to aid HOT starting. By keeping the fuel rail pressurized, it prevented fuel boiling from engine "heat soak", thus reducing the chance of a "vapor lock".

And the pressure hold time spec is measured in minutes, i.e. it's not meant to hold pressure overnight.
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Ok, the check valve is a non-issue, then. I will try to get to the temp sensor measurements, but since this does not happen very often I suspect I will have tough time catching it. It seems like the dual temp sensor (the one that matters) is not so easy to replace, so it would be nice to be sure it is bad before going after it. The CPS, I am really not all that sure is a culprit here. I've had bad CPS before (not on this vehicle) and the symptoms are mostly present during running, not starting. If the ECU does gets a bad signal from CPS the engine just misfires, doesn't idle, etc. This is not at all what I am getting. I am getting a symptom where the engine cranks and does not start or even try to start (as in catch and stall). Then, after a few attempts it starts as if nothing is wrong. and runs all day long with no more incidents. Then the symptom may not repeat for weeks. I would think a bad sensor would be much more persistent in its character, but I may be wrong.

I'll find the pins 13 and 5 and have a meter ready next time I get a no start. See where that leads me.

Thanks.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

"I am getting a symptom where the engine cranks and does not start or even try to start (as in catch and stall)."

Then that's when you must check for spark (or not) at one of the plugs. If there is spark, then you can dismiss the CPS (without which there can be no spark) and look for a fuel-related problem. IMO, this should be the first step in ANY no-start analysis.

Until you've verified a good spark when cranking, all this fuel-related chatter is a waste of everyone's time. Regina Ignition problems are less frequent than fuel, but it's a mistake to assume fuel, sensors, etc. on every no-start

And I'm not sure your assumption about what a "bad CPS" does is valid. Since, as I've said about some FAQ descriptions, it's based only on your one individual experience.
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Did you try switching on the car first (position II)without cranking? the fuel pump works for 2 seconds and stops each time, do this twice or 3 times and then start the car. If it starts fine doing this then it's the pump.

Also check the fuel pump relay, behind the ash tray, big white box, second row to the left side, put your left hand fingers on it and move the key to pos.II, you should feel the internal contacts clicking.

Regina uses only one in-tank pump, be careful when you buy it because they can give you the wrong one. It doesn't come with a strainer (filter.

Also, the original pump has it's embedded fuel check valve, don't know why the aftermarket pump lets the fuel return back to the tank and it'll be hard to start after a few hours unless you add a check valve in the system.

Replacing the pump is tricky but doable.

If I do replace, isn't there an OEM pump out there with the check valve? If I must go with aftermarket, how do I introduce the check valve in there? Also, does the strainer from the old one fit the new one? Is it possible that I just have a clogged strainer making the pump work harder? Can I just get at the strainer and try cleaning it and see if that give the pump a new lease on life?

Thanks.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

It's a matter of money, the OEM "best" pump is much more expensive than the aftermarket pump, check FCP_Groton and eEuroparts.com (remember for Regina cars).
The filter can be re-used but it's so cheap that I wouldn't do it, if you get to that strainer you'd better replace the pump.
Some pumps need soldering the cables to each pole (be carefull don't connect them to the wrong pole or the pump will run the other way).

Read the FAQs, they are good on this matter.
As they've said, check for spark in the morning with another plug grounded (buy a new one or take an old one)and also check for gas in the return short hose that leaves the Fuel preasure regulator.

Remember the car only needs 3 factors to start: Gasoline from the injectors, spark and movement from the starter, and of course assuming the timing belt is good, which is out of the question in this case.

hello
if your at 200,000 your are past the point where many here have allready had thier rex/regina pump go south.
you could check fuel pressure or current draw to pinpoint.
good luck
mike
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95 944T, 94 945T, 85 244T.

How do I check fuel pressure and current draw? I am both mechanically and electrically inclined (am actually a EE), just ignorant. I do have a good DMM to measure current, but no tools to measure fuel pressure. Any advice? I am not against buying a new tool to keep my Volvo running. Still cheaper than taking the car to a mechanic.

Thanks.
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Vladimir. '98 S70 base, 5-speed manual - his, '93 945 (approaching 200K miles and rolling on...) - hers

If this is a wagon its not too hard if all the hoses are still flexible&the clamps can be removed.The screen probably is totally clogged&pump would not have been running because of that.Change it&save the old one for a backup.

You can get a replacement for $105 plus shipping from fcpgroton (fcpgroton.com). You will also need the filter sock, just a few bucks.

Read the faqs, it really helps. I just changed my daughters last weekend with 150K miles. They are good for about 155K to 175K, at least that is my experience. I have changed three and the problems I had were getting the ring off the neck of the fuel tank. Very important is to mark the ring's relation to the tank and the lid the ring secures (I used whiteout, typing type). This will make sure everything goes together and that the ring isn't overtightened and broken. I used a 1 X 2 to pry the little protrusions on the ring by leveraging it between the protrusions and the side of the car's metal opening to the pump. Another frustrating problem is getting the pump out and in. It will go, but for putting it in, make sure the cotton string or whatever collapses the spring part (you'll see it when you get it out).

I have read that the wagons are easier, but don't know firsthand.

I agree with the other post i.e. you are long overdue in replacing the pump.