I checked the archives, did not find a solution:

Last run yesterday was a 45 mile jaunt, so the lawn mower syndrome can be ruled out. This morning, I had to crank the car, probably 45 seconds, to get it to start. The last 35 or so was with the throttle pedal to the floor, and then it was rough running for several seconds until it cleared out and ran fine. Every start since then today was hard, but not that bad, maybe 10 -20 seconds. The longer the car sat, the more difficult the start.

This afternoon, I checked for codes, A2 and A6 were 1-1-1. I cleaned the MAF, started the car and ran it a minute, then left it alone for an hour. Then it was hard to start again.

I pulled the plugs, they look OK< but have about 30K miles, so it's about time to change them. Plug wires (Bougicord), cap and rotor (Bosch) are all under 3 year old. The FPR is about a year old, as are the vacuum lines and PCV system. All seem to still be connected.

Any ideas where to start?

Somehwre in this episode, I mentioned the problem started soon after a fresh tank of gas.

Friday, I filled again, and did not notice a change, but I only started it once or twice.

Yesterday it started normally the three times I drove it.

This morning it started normally when I pulled it into the garage to change the blistered plugs and carbon tracked dizzy cap. Not only that, but although the plugs still had blistered insulators, the color was back to a more normal tan instead of burnt white.

I dunno what was in that tank of fuel, but I'm glad it's gone. We'll see how the car does this next week.

Ron

Well a few days of good starting went wrong again, so the bad fuel idea was ruled out. I pulled my old fuel pump out of the parts bin, fixed the leak (It leaked every time I had a full tank) and put it back in. It's been great for several days now, so the whole thing appears to have been the fuel pump check valve after all. Hopefully I have the leak fixed as well.

I'll post again if the problem ever recurs.

Glad to hear you got it fixed. Let's keep our fingers crossed.

I think if I ever end up pulling my pump again I will order a new flange gasket as a matter of course - they seem to get old and flimsy and leak. It's a real pain trying to get an old worn out one to seal compared to a new one, and they're not too expensive.


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1998 V70 AWD->FWD Turbo 200k+

OK, here's today's status:

Recehecked all vacuum lines, checked for vacuum leaks both with stethescope and with carb cleaner...no leaks.

Compression remains good between 170 and 185 PSI, hot.

Dizzy cap has minor carbon tracking, a new one is on order. If this were the problem, I'd think it would show at more than just starting.

Spark plugs: NKG BKR6EK...the heat range is right, but don't know what the last two letters mean..they are different than recommended, but have been fine for 20,000 miles until this started. All electrodes are fine, little ash or oil build up, but the center porcelins are blistered. Since the heat range is correct, I have to assume the car is running too lean, which sort of is the way the starting seems...way too lean. But I have no vacuum leaks, (see above). New Volvo plugs are also on order, Bougicord wires have about 30,000 miles. PCV system was replaced 11,000 miles ago

Fuel pressure regulator was replaced within the past year, and the system holds pressure per Klaus' instructions.

It's still hard to start, sometimes just needs to crank 15-20 seconds, and then it''s fine, other times it starts firing one cylinder at a time until it catches. either way, once it's running, it's fine.

So where do I start looking now?

The best thing to do would be to simply check the fuel pressure at the rail before you start it. You can simply press on the valve at the end and see if it sprays out with any great force, or use a fuel pressure gauge for better judgement.

I had a problem with the FPR on mine, but it was causing the car to throw codes for fuel trim and all sorts of strange things were going on. Pull off the vacuum line to the above-mentioned regulator (shield your eyes first...don't ask how I know!)...if fuel spurts out of it, you need to replace the regulator.

BUT if that checks out ok, it may be the check valve on your fuel pump is causing the system to lose pressure that has to build back up when you turn the key, thus causing the hard starting. Unfortunately, the check valve is a part of the whole assembly, and the whole thing must be replaced ($$$).

I have heard tell of people using an in-line check valve to splice into the fuel line. I have never used one myself, but such a device would do exactly the trick you need it to.

You get the prize! No pressure at the fuel rail after 1/2 hour. NOw to get one of those 740 check valves and splice it in...

Sorry Champ, but there shouldn't be ANY pressure after 1/2 hour. The check valve will not hold pressure, but it will keep any fuel in the line from flowing back into the tank.

The check you want to make: after a short time period, push on the schrader valve and a little dribble of gasoline vomes out. Then turn the key to position II to 'prime' the pressure, push on the schrader valve and see the spray - use a shop cloth please.

If there is no pressure after you turn the key to pos II, try a check valve.

Klaus
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Praying for Cynthia Amendt, heaven bound

you might want to check how long it takes for the pressure to run down though.

I had a pump that was not holding pressure a while ago. I found the results of testing with a fuel pressure tester interesting.

The 'broken' pump that wasn't holding pressure would lose all the pressure right away. Turning the key to posII and letting the 'prime' happen a few times, I could build the pressure up to about 35 psi which should be fine to start. But as soon as it got there, and the pump shut off at the end of the prime cycle, the pressure would start too fall off right away. Basically all the way down to 0 psi.

When I got the new (to me) pump in, it would build right to almost 40 psi on the first prime cycle. And when the pump shut off the pressure would basically stay the same. It would take about a half hour for the pressure to slowly leak down to 'very little' which I think was down around 10 psi.

So a fuel pressure gauge might give you some more information about what's going on in there.

As KlausC says, the real issue is whether there is still fuel in the line from the pump to the injectors - the pump can do it's thing in a couple seconds if it doesn't have to refill the line.

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1998 V70 AWD->FWD Turbo 200k+

Ah, so not like the old Bosch CIS systems. Without holding the pressure, how does the system avoid heat soak vapor lock?

It's raining again, so it may be a while until I can check it.

Thanks for your insight!
Ron

Unlike my 164 with the fuel rail running the length of the 6 cylinders, twice, the 5 cyl engines only have a foot of line going across the intake side of the engine. Not quite hot enough for vapor lock.

Holding pressure at the pump is too costly and difficult and not needed. The pump easily exceeds 43psi in less than 1 second so that required pressure for the injectors is always there.

But, if the fuel drains back to the tank, the 2 second prime during key posII time is not enough to send fuel to the rail and build pressure.

If the car won't start right away, try turning the key to posII a few times and listen to the pump do its thing. If it then starts, the fuel is probably returning to the tank.

If it still has a hard time starting, have you checked the spark plugs lately?

BTW, the sun made its appearance, first time in 7 days!!

Klaus
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Praying for Cynthia Amendt, heaven bound

Timely response, Klaus, I just came back in from checking pressure. The car had been sitting a couple of hours, and yes, without turning the key, I got a few dribbles. Turned the switch to II, and I got a healthy squirt. Switched it off and a minute later, still had pressure. The I tried to start it, it was pretty hard.

Thinking of all of out wet weather, I thought about ignition problems, so tonight after it gets dark, I'll run the car in the dark and look for any coronas. Still, once it's started, it runs fine. I did check the plugs when this started, and while they aren't new, they aren't bad. Tip color is good.

Also, it really starts like it's lean rather than flooded, and it's not really not like an ignition problem anyway. It's like one cylinder will catch, then the next and the next until it runs smooth. Think of a Curtis Wright Cyclone in a B17....Pop!. Pop pop! Popopop! popopopop!chugachugachugachuga ROAR! No black smoke from the tail pipe, though even though it only has 119,000 miles, it's been an oil burner for a while (see prior posts from last year) and there is some blue smoke at start up. compression last year was still good, I've not checked it yet this year.

Maybe the coolant temp sensor is bad and making it start lean? It's raining AGAIN, so testing it will have to wait. I can't wait to get my garage back from the storage building it's become.

I did unplug the IAC and cam sensor, the sockets looked good, but I still hit them with electrical cleaner. No change.

An excellent analogy, if I do say so myself. B-17's are my favorite plane ever aside from the P-51 Mustangs.

I wouldn't think that the coolant temp sensor or cam sensor...or really any sensor for that matter would cause that kind of starting up. It sounds like its starting rather like a car starts up after being lawnmower-syndromed.

As a matter of curiosity, if you can pull out the whole injector rail after the car's been sitting for some time, hold it over a bucket and turn the key. Do some of them just squirt air before they start spurting out fuel?

As a matter of fact, it is very much like when I've lawnmower syndromed the car. Yet I can't imagine the lifters leaking down like that, and all of the sudden. It's gotten regular oil changes, always either Volvo or Mann filter, and I've AutoRx'd it,it is very clean inside, so we can rule out sludge.

Monsoons play havoc on the rotor & distributer.

Klaus
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Praying for Cynthia Amendt, heaven bound

I really need to check my spelling before pressing send...sorry.

It's been raining fairly ahrd the past 2 days, so I've not had much chance to look at things. I did pull the vacuum line off of the vacuum tree, and tho there was no liquid gas, I did notice that there was a distict gasoline smell to the line when I cecked to see if it held vacuum. sure using you mouth is dumb for this, but I wouldn't know abou the gas smell either.

Tomorrow I'll check and see if I have pressure on the rail overnight or after an hour os so too.

Is FPR fuel pump relay or fuel pressure regulator? The regulator is under the fuel rail and has a clear vacuum line that goes to the tree. If there is gasoline in it, replace the regulator because it is leaking gas into the manifold.

Klaus
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Praying for Cynthia Amendt, heaven bound

Hah! Too many acronyms, too easy for different things to have the same one.

I replaced the fuel pressure regulator, Klaus. I guess I could chck to make sure it didn't go wrong

you might want to try the camshaft sensor. It is on the back end of the exhaust cam held in place by 2 torx screws. Check the connector. This is a hall effect sensor and I have had them go goofy in the past. Good luck and be sure to let us know what cured the problem

Cam sensor is only a few years old too, and no codes. I am thinking more along the lines of teh Fues pressure regulator or check valve, but it's been raining for 2 days. Maybe this weekend I can get it in the garage and have a look

I'm grasping at straws here, but if it runs well once it gets started, I would check electrical connectors for the rpm and cam sensors, but especially around the throttle and IAC. Sometimes just pulling a connector apart and reseating it is enough to fix a slightly corroded contact. Also be sure both the throttle body and IAC are clean and operating easily.

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'96 850 and '83 244 DL both at about 200K; gone but not forgotten '81 245 and '64 Amazon

That is easy enough to do and I will try it, but wouldn't a bad connection give a bad signal and thus throw a code? just curious, it'll only take a moment to clean both.

There are codes for both the IAC and the throttle position sensor, but I don't think they would necessarily be tripped if it's an intermittent problem that goes away once the engine is warm. It's interesting that the IAC in my '97 850 looks not much different from the one that was in my '81 245, so I don't know that there was much new in the way of sensor circuitry. In fact, when I did the PCV system, the IAC was pretty well stuck closed, but didn't throw any codes. The TPS may be a different story, as there are three codes for it. Nevertheless, just because you don't get a code doesn't mean it's working entirely well. Keep us posted on your progress, I'm sure others will want to know!

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'96 850 and '83 244 DL both at about 200K; gone but not forgotten '81 245 and '64 Amazon

If teh IAC were stuck/clogged, whatever, wouldn't the idle speed be off?

Probably so. If you have a nice smooth idle once it starts, that's probably out of the picture. The only scenario I can think of then would be if the IAC doesn't close when the motor is turned off, the excess air going to the throttle might make it hard to start.

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'96 850 and '83 244 DL both at about 200K; gone but not forgotten '81 245 and '64 Amazon

First see my second post down from the top. I double checked with NGK, the plugs I have are the correct heat range, so it IS running lean or having pre-ignition problems. Since I can't set the timing, it must be lean, right?

Also, this started soon after a new load of gas..what are the odds that bad gas could make it hard to start, but still have it run right?

I still have my old fuel pump, it worked fine but leaked where the wires came out of the assembly. The replacement was a junkyard special. I'll try the old one and see what happens.

If that does not work, then I'll try my old fuel pressure regulator. I replaced it under a WAG for another problem, which it did not solve. Of course the first thing is to put in the new plugs, cap, and rotor.

Thanks for all of the ideas everyone.