On Tuesday, I drove 200 kilometers with the station wagon. No worries. But when I got back to the city, the idle speed started to go up and down, between 500 and 1300 rpm, just like that. I was able to bring the car back at the cost of over-consumption of gas. I deduced that this was due to the MAF.
In your opinion, this type of engine behavior, could it be the MAF, the cause of the failure? (I looked at it when I took out the air box, it is perfectly clean and no dirt on it, nor in the duct).
The spark plugs, the harness, the rotor, the finger are new. On the injection side, all the gaskets are new, and the injector filters have been changed. The PCV kit is new.
I think my vacuum system is good (I have to check it again).
But it could be an air intake...
Any idea what I should check?
850 1995 Idling up and down Topic is solved
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misha
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- Year and Model: '97 850 2.5 20v
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Disconnect Maf connector and see if the idle returns to normal.
Since you replaced PCV system recently...it could be that you have a vacuum leak somewhere.
Since you replaced PCV system recently...it could be that you have a vacuum leak somewhere.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
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
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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850oldschool
- Posts: 392
- Joined: 19 October 2019
- Year and Model: 1996 850 NA
- Location: Minneapolis, MN
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I diagnosed my bad MAF by watching the graph of the output on my scan tool.
Many lower cost units have this capability.
Many lower cost units have this capability.
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manovlov
- Posts: 1180
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- Year and Model: 1995 850 GLT 2.5 170
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I don't think i can plug a scan tool on my 95.850oldschool wrote: ↑04 Dec 2022, 10:53 I diagnosed my bad MAF by watching the graph of the output on my scan tool.
Many lower cost units have this capability.
1995/02 850 GLT 2.5 170 Petrol M56
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850oldschool
- Posts: 392
- Joined: 19 October 2019
- Year and Model: 1996 850 NA
- Location: Minneapolis, MN
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My car is a 96.
Do you have the 16 pin connector under the coin holder next to the cigarette lighter?
Do you have the 16 pin connector under the coin holder next to the cigarette lighter?
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misha
- Posts: 5379
- Joined: 7 December 2008
- Year and Model: '97 850 2.5 20v
- Location: Serbia
- Has thanked: 152 times
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Jetronic management is obdI.
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
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
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
-
manovlov
- Posts: 1180
- Joined: 6 July 2011
- Year and Model: 1995 850 GLT 2.5 170
- Location: Grenoble, France
- Has thanked: 620 times
- Been thanked: 143 times
Nope, i have this :850oldschool wrote: ↑04 Dec 2022, 12:48 My car is a 96.
Do you have the 16 pin connector under the coin holder next to the cigarette lighter?
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1995/02 850 GLT 2.5 170 Petrol M56
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manovlov
- Posts: 1180
- Joined: 6 July 2011
- Year and Model: 1995 850 GLT 2.5 170
- Location: Grenoble, France
- Has thanked: 620 times
- Been thanked: 143 times
News.
MAF unpplug, the engine turns low(about 500/600/700 RPM) then stop.
Idling MAF plugged
MAF sensor itself
MAF unpplug, the engine turns low(about 500/600/700 RPM) then stop.
Idling MAF plugged
MAF sensor itself
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1995/02 850 GLT 2.5 170 Petrol M56
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misha
- Posts: 5379
- Joined: 7 December 2008
- Year and Model: '97 850 2.5 20v
- Location: Serbia
- Has thanked: 152 times
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Do not unplug the connector while engine is running!
Remove connector,start the engine.
If the idle is stable and runs better with Maf unplugged than it is bad.
In your case....since you did a pcv job recently...i would check if there is a vacuum leak somewhere.
Pcv valve,intake manifold,vacuum tree,main big plastic hose from airbox to throttle body,fpr vacuum line.
Read the codes and post them here so we can see what's going on.
Did you plugged in a TPS sensor connector after pcv system replacement?
Remove connector,start the engine.
If the idle is stable and runs better with Maf unplugged than it is bad.
In your case....since you did a pcv job recently...i would check if there is a vacuum leak somewhere.
Pcv valve,intake manifold,vacuum tree,main big plastic hose from airbox to throttle body,fpr vacuum line.
Read the codes and post them here so we can see what's going on.
Did you plugged in a TPS sensor connector after pcv system replacement?
'97 850 2.5 20v / fully equipped / Motronic 4.4 from the factory / upgraded with S,V,C,XC70 instrument cluster / polar white wagon
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
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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