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94 850T check engine light while accelerating

Help, Advice and DIY Tutorials on Volvo's extremely popular car line -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

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henrysin44
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henrysin44

Re: 94 850T check engine light while accelerating

Post by henrysin44 » Tue May 12, 2020 7:13 pm

RickHaleParker wrote:
Tue May 12, 2020 6:57 pm
henrysin44 wrote:
Tue May 12, 2020 6:49 pm
Don't exactly know how that could cause a CEL after a week but the cluster has always acted up for years now.
Cracked solder joint, path or connector got aggravated when you pulled the cluster.
Hopefully so, the solder did look like cold joints, I'll try out another cluster tomorrow
http://shealabs.net
Daily driver Black 1994 Volvo 855 2.3L Turbo - manual swapped, turbo swapped, green injectors, custom M4.4 Tune, de-catted, custom two-tone interior, V70R seats & rims
Teal 1994 Volvo 855 2.5L N/A Manual Transmission (the back up daily and parts car) - Runs and Drives but the engine knocks
Silver 1997 Honda CRV 2.0 AWD - its in a very sorry condition, but drives
Silver 2003 Subaru Forester 2.5L N/A AWD - Leaks everything

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misha
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misha

Re: 94 850T check engine light while accelerating

Post by misha » Wed May 13, 2020 3:16 am

henrysin44 wrote:
Tue May 12, 2020 6:49 pm
...Don't exactly know how that could cause a CEL after a week but the cluster has always acted up for years now.

As a side note not all the lights come up when key is in position 2, or while starting, but all are functional.
That cluster is bad and you will need to replace it.
Could be a bad connector to the cluster or cold solders on the cluster.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

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BEJinFbk
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BEJinFbk

Re: 94 850T check engine light while accelerating

Post by BEJinFbk » Wed May 13, 2020 4:05 pm

Dumb question - Are you sure it’s the CEL?

This sounds like exactly what happens when
you get low on windshield washer fluid.
If I catch it out of the corner of my eye,
sometimes it tricks me...
'98 V70 R - Well Equipped for Life Up North... ;)

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misha
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misha

Re: 94 850T check engine light while accelerating

Post by misha » Wed May 13, 2020 4:29 pm

That light is on the opposite side of the cluster.
However...his cluster is not working properly....just 2 or 3 lights on bulb check and all of them are replaced and checked.

It's either a connector or cluster is bad.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

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henrysin44
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henrysin44

Re: 94 850T check engine light while accelerating

Post by henrysin44 » Thu May 14, 2020 3:15 am

Yesterday I replaced the knock off RPM sensor with an OEM sensor. There is no change from doing it, CEL still comes on during hard acceleration, but im glad i swapped it out, doubt the knock off would last much longer. Maybe I just need new spark plugs? Theyre coppers and im pretty sure ive been running them for at-least 10K.

As for the cluster, its not defective :D . I did however figure out why the key-on lights don't come on! When the battery/charging light comes on it will also turn on most of the dash warning lights, which would also explain why the key-on lights come on if the alternator belt snaps. (pic below). So my battery light isn't getting a signal from the charging system, which doesn't bother me yet.

EDIT: The alternator signal wire was disconnected, now my dash shows all the warning lights when in position 2. Still have a CEL on acceleration though.
Attachments
cluster.png
Cluster Diagram
http://shealabs.net
Daily driver Black 1994 Volvo 855 2.3L Turbo - manual swapped, turbo swapped, green injectors, custom M4.4 Tune, de-catted, custom two-tone interior, V70R seats & rims
Teal 1994 Volvo 855 2.5L N/A Manual Transmission (the back up daily and parts car) - Runs and Drives but the engine knocks
Silver 1997 Honda CRV 2.0 AWD - its in a very sorry condition, but drives
Silver 2003 Subaru Forester 2.5L N/A AWD - Leaks everything

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misha
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misha

Re: 94 850T check engine light while accelerating

Post by misha » Thu May 14, 2020 9:07 am

It should...because if the warning light doesn't work...your alternator will not have output.
The light works as "awakening" for alternator.

EDIT...i just saw that you re-connected the wire.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

Chuck W
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Chuck W

Re: 94 850T check engine light while accelerating

Post by Chuck W » Thu May 14, 2020 1:24 pm

How long have you been driving it since the battery disconnect?
It could clear up after the ECU readjusts a bit.

You could have a sensor that is out of spec, enough to cause an issue when the ECU is reset, but will then clear up after a while. My M4.4/green injector-swapped '97 does the same thing. It would "reset" after having the battery disconnected for a time and then would flash the CEL at me on acceleration for a few drives until clearing up.

How old is the Engine Coolant Sensor? When was the last time you checked the connector?

I think with the M4.4 ECUs that flashing on acceleration is a knock sense reaction.

Misha is much more an expert on this stuff than I am, though.

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henrysin44
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henrysin44

Re: 94 850T check engine light while accelerating

Post by henrysin44 » Thu May 14, 2020 3:55 pm

misha wrote:
Thu May 14, 2020 9:07 am
It should...because if the warning light doesn't work...your alternator will not have output.
The light works as "awakening" for alternator.

EDIT...i just saw that you re-connected the wire.
That would definitely explain why my headlights would be dim until i started driving.
Chuck W wrote:
Thu May 14, 2020 1:24 pm
How long have you been driving it since the battery disconnect?
It could clear up after the ECU readjusts a bit.

You could have a sensor that is out of spec, enough to cause an issue when the ECU is reset, but will then clear up after a while. My M4.4/green injector-swapped '97 does the same thing. It would "reset" after having the battery disconnected for a time and then would flash the CEL at me on acceleration for a few drives until clearing up.

How old is the Engine Coolant Sensor? When was the last time you checked the connector?

I think with the M4.4 ECUs that flashing on acceleration is a knock sense reaction.

Misha is much more an expert on this stuff than I am, though.
I've drove about 150 miles total sense the reset, the coolant sensor is only about a year old and I re-did the connector wiring when I replaced the sensor.
I really hope the CEL is not a reaction to a engine knock, engine sounds healthy though.
http://shealabs.net
Daily driver Black 1994 Volvo 855 2.3L Turbo - manual swapped, turbo swapped, green injectors, custom M4.4 Tune, de-catted, custom two-tone interior, V70R seats & rims
Teal 1994 Volvo 855 2.5L N/A Manual Transmission (the back up daily and parts car) - Runs and Drives but the engine knocks
Silver 1997 Honda CRV 2.0 AWD - its in a very sorry condition, but drives
Silver 2003 Subaru Forester 2.5L N/A AWD - Leaks everything

Chuck W
Posts: 299
Joined: Wed Dec 24, 2014 10:45 am
Year and Model: 97 854 T5
Location: Indianapolis, IN
Has thanked: 21 times
Been thanked: 44 times
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Chuck W

Re: 94 850T check engine light while accelerating

Post by Chuck W » Thu May 14, 2020 4:43 pm

I guess it's also possible that you had low voltage going to your ignition system, which could cause an issue when the engine was under load.

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misha
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misha

Re: 94 850T check engine light while accelerating

Post by misha » Thu May 14, 2020 5:17 pm

henrysin44 wrote:
Thu May 14, 2020 3:55 pm
...That would definitely explain why my headlights would be dim until i started driving.
You had a good luck that your battery was in good shape.
Since you ran a car with low voltage charging system...i would suggest to remove negative battery terminal for a few hours in order to reset car's management system and all bad things it could catch because of low voltage.

After that,perform a re-learning procedure for ecu and check voltage output on battery terminals.
Re-learning procedure:
http://www.volvotips.com/index.php/850- ... rocedures/
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
'91 Citroen XM 2.0 SI /fully equipped/mandarine red metallic
History of Volvos in the family:
'71 144 S
'73 144 De Luxe
'78 244 DL
'78 244 DL
'79 244 GLE
'85 340 GLS

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