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Hey all,
After a few short trips during the day, on a final errand the car was running fine for about a mile after a warm start when the engine completely died and all panel lights came on. It restarted and ran for another 15 seconds or so, enough time to get it out of traffic. Subsequently it was towed into my driveway.
Following the typical script, here's where I am at:
- Fuel pump relay clicks closed and allows main pump to audibly "prime" when ignition is turned ON
- Fuel pump seems to run during cranking, and I hear the relay click open a couple of seconds after stopping cranking per usual. So Hall sensor seems good.
- Visual confirmation: Crankshaft is turning while cranking, so timing belt is good.
- No trouble codes stored in ODB; basic ODB tests "pass"
- Power stage connector is clean and proper.
- Spark plug wire pulled from plug and held close to engine block delivers spark; not sure how much spark to look for, but to me it seems a little weak
- With ignition coil connections removed and fully cleaned, coil delivers 11v at ON (between T15 and ground as well as T1 and ground). Is the fact that it's one shy of 12v enough to prevent starting?
- Resistance test of coil shows 1.3 ohms for primary (vs. the .6 to .9 range specified in the FAQ. Is the fact I'm over by .4 to .7 enough to prevent starting?) Resistance of secondary is 7.6K ohms (within the 7.0 to 8.5k range stated in the FAQ).
What do you think; is the coil marginal and keeping the ignition from starting? If so I can swap it. Or do you think it's probably "good enough" and I should move on to troubleshooting the FP relay contacts and pumps themselves?
Thanks for your thoughts.
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To close out this thread: The issue was not resolved, although the advice was leading me down a good path. The car had been destined for disposal, and instead of going out with its boots pointing forward, it went out with boots pointing backward (via a flatbed to a parts yard, with most proceeds going to public radio). See my post "Time Is Up for This Brick." Sincere thanks to everyone who assisted with troubleshooting.
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Hi,
"After a few short trips during the day, on a final errand the car was running fine for about a mile after a warm start when the engine completely died and all panel lights came on"
Are you using Bosch copper plugs, preferably the ones suited for turbo? Non-standard plugs may foul easily especially on doing short trips. One precaution is not to use Bosch Platinum plug - the first generation type which has its centre platinum electrode embedded within the porcelain tip. This plug's tip may foul with carbon which results in weak spark and non-start condition.
Amarin.
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Hi Amarin,
I'm using Bosch copper. I haven't replaced them in a while so while check for constancy of spark, I'll pull at least one and see if it's unusually dirty/fouled.
Thanks.
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Why don't you pull the diagnostic codes ?
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Do you get one spark or a bunch?
I keep an extra plug in the cars so that I can check for spark - It need not be a plug for your car, just set the gap properly.
Have you pulled codes and done the testing if you have the little test box in your engine compartment? My car passed all tests and had no codes when it would not start.
If your timing belt has skipped a tooth or two - or if teeth are missing - the cam will turn, but not act properly. How old is your timing belt? Most people have never seen their timing belt - you may be amazed at how small and fragile it looks!
When I had a problem with our '90 744TI, all I got was one spark. Turned out that the computer was gone. The junk yard that with over 700 Volvos - had 150 computers for NA 740s, but NONE for turbos - they could not find one on their network either.
Another timeI had a ground problem for the ignition - my car stalled when the high beams were turned on - its in the FAQ! When I cleaned all the grounds in the left front fender (there was one at the base of the anti-lock frame) I checked the battery connections - the main wire and the small wires on the positive post were badly corroded - I cut some crud off and soldered them to the post connector.
Good luck and hope it is not the computer.
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Hi James,
I do get a bunch of sparks. Will analyze further! I wonder if the coil being out of spec on the resistance test if affecting spark. Output of the coil (11v) is the same as the battery, per my voltmeter.
Thanks,
- G.
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I'm with Spook on this one. Somewhat similar to my experience with a battery that ran down because the alternator was failing. No sign from the alternator light that it was, indeed, failing. Instead I was diverted to transmission and ABS trouble by the warning lights when what was really at fault was a weak battery caused by a failing alternator.
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Will it fire up momentarily on starting fluid?
If the pumps run and it won't start but responds to starting fluid I would resolder the radio suppression relay.
Randy
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Any twenty minute job is just a broken bolt away from a three day ordeal
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Randy,
Good thoughts.
Remind me, where best to shoot in some starting fluid?
Also, if you have any info on where to locate that radio suppression (fuel injection) relay, that would be great.
Thanks very much.
-- G.
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Not sure if this applies to your turbo 9-series, but I shoot the starting fluid into the port where the hose for the fuel pressure regulator originates, then put the hose back on.
--
Art Benstein near Baltimore
'Some people ask the secret of our long marriage. We take time to go to a restaurant two times a week. A little candlelight, dinner, soft music and dancing. She goes Tuesdays, I go Fridays.'
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It is clipped up under the top of the fender just back from the battery. It is black and silicone sealed to its case.
Randy
--
Any twenty minute job is just a broken bolt away from a three day ordeal
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Dear GregR,
Hope you're well. The failure mode you describe suggests that prior to the stoppage, the car was running on battery alone, i.e., that the alternator stopped charging the battery. Eventually, the battery's stored energy was expended and the car stopped.
Some questions:
(a) How old is the battery?
(b) Are the battery's posts and cable clamps corrosion-free?
(c) What does a volt meter show as the battery's charge?
(d) How old is the alternator (year and mileage)?
(e) Is the alternator drive belt in good condition and properly tensioned?
(f) Does the crank pulley's steel center (core) turn independently of the rim?
As to (f), if the crank pulley is the factory-installed unit, the rubber - that bonds the steel core (through which passes the hex bolt that secures the pulley to the crankshaft - may have failed. That failure cuts the power transmission from the core to the grooved rim, on which ride the drive belts.
If so, the alternator, water pump, and power steering pump may turn more slowly than normal. So, the battery will be under-charged as the alternator is not turning at normal speed.
To check the crank pulley's condition, use white paint to draw a line from the center bolt out to the outer edge of the pulley's "face". If you can cause the engine to crank, and the single white line becomes two separate segments, the crank pulley has failed.
Please post your findings.
Hope this helps.
Yours faithfully,
Spook
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Hi Spook,
Thanks for your thoughts.
The car will crank fine, and did so prior to the trouble so far as I could tell.
The battery is about a year old (replaced a Volvo battery that had been in the car for 20+years, no kidding, in Chicago yet!).
During my restart attempts I sapped it a bit, so yesterday I put a charge on it. On the DMM I pulled 11 volts after charging--same as the 11v read from the ignition coil primary. All contacts and connections are clean, but I'll pull the connectors off the posts to double check.
Going back to the original question: Assuming my cheap-o DMM is accurately, is 11v from the ignition coil insufficient to run the car?
If so, I'll replace the coil. If 11v and decent cranking should be enough, I'll go Randy's route and either try to start with starter fluid (haven't done that in about 40 years, to an old Ford V-8!) or at least try to check fuel pressure at the rail if I can look up how to do that with a gauge borrowed from Auto-Zone.
Thanks all for the great input.
-- G.
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Dear Greg R,
Hope you're well. To test your Digital Multimeter (DMM), take a factory-fresh 1.5 volt battery and see if the meter shows at least 1.5 volts. If it does, the DMM likely is OK.
If, after charging, the battery showed only 11 volts, there's a bad cell in that battery. Even if it is just a year old, something has gone wrong.
Some auto parts stores can load-test batteries. If such a test shows 11 volts, then the battery is "junk".
One other thought: I've read posts wherein it was reported that corrosion under battery cable insulation sheaths caused inadequate power flow.
As to the coil, if you have handy a known-good spare, it is an easy swap. Few coil failures show in on this board.
Another possibility is that the fuel injector relay (on the inner-fender wall of the engine compartment) may have failed. If so, the car will crank but not run.
Hope this helps.
Yours faithfully,
Spook
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Thank you Spook so much for your time. It's always appreciated.
If I'm reading you correctly, and if the DMM is accurate, then 11v at the battery and subsequently from the coil is likely not good enough to operate ignition (or perhaps not enough given aging components such as cap, rotor, plugs etc.) Agree?
The battery is an Everlast (Johnson) from Walmart, one without an auto center, , but I can take it in to Autozone and see how it tests.
I don't have a spare coil. The resistance readings are off but I'm not sure if they're "that bad."
Thanks again,
- G.
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Way too many coils have been changed needlessly because of those resistance "specs" and car owners applying a common multimeter to read them.
Unless you can test your meter's calibration with some precision resistors, in the range you're using it in, take those measurements with a grain of salt. Definitely don't buy a coil because it measures 1.5 ohms, and remember the temperature (internal) makes that number vary quite a bit.
Soapbox item for me would be to insist every consumer-targeted DMM come with a small assortment of resistors to check each range, in the same vein as Spook's suggestion to test the voltage scale with a battery. Once you accidentally measure resistance on a powered circuit, the meter's probably incurred damage.
I've worked on a lot of Volvos and have yet to come across a Bosch ignition coil that needed replacement.
--
Art Benstein near Baltimore
Two secrets to keep your marriage brimming
1. Whenever you're wrong, admit it,
2. Whenever you're right, shut up.
-Patrick Murra
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Dear Greg R.
Hope you're well. A battery that - after charging - reads 11 volts at the battery's terminal posts - is "toast". It should read 12.5 volts or more. Even so, I'd have it load-tested, to be sure.
The fuel injectors' relay - a.k.a. the radio interference suppression relay - is a very dark brown (almost black). It is mounted on the passenger-side inner fender wall, just to the rear of the headlamp housing (non-turbo model) and, on cars with a turbo-equipped engine, just to the rear of the headlamp housing on the driver's side. A metal clip secures the relay. The four-wire connector may separate unwillingly from the relay, so be gentle and patient.
If this relay is the factory-original item, it doesn't owe you a penny after 25 years of service.
Hope this helps.
Yours faithfully,
Spook
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