V70 2.4 1999 NA misfire?

[Themapinspector]

Hi all, first post here. I own a 1999 V70 2.4 (170hp) which I’m bringing back onto the roads. Most things run fine except an issue with the engine. When starting it’s all fine, runs smooth as glass. Though when I request throttle there is what feels like a misfire. This is constant although there are certain circumstances this doesn’t happen. If I’m at high revs and I can give the car a good amount of throttle before the misfire starts. Eg at 6k rpm I can use all throttle. Pulling off from junctions at 1-2k I can barely touch the throttle at all. I’ve replaced all plugs, and have unplugged each coil and injector one by one while revving and I can’t seem to pin one that has an issue, I was under the impression that if one coil or injector was faulty, then I could unplug that one and it would make no difference (under the given circumstances of course)

There is a second issue, I’ll call this throttle delay. I hit the pedal and the engine cuts out for about a second before coming back in. Im looking for vacuum leaks at the moment as I have fixed 2 so far (one on brake cylinder and one on a random sensor at the front of the engine)

Thank you for reading and any questions I will answer to the best of my knowledge. I also own MGs and do major work on their engines, although moving to the Volvo platform has me completely stumped

[Themapinspector]

Sorry here’s some more info
Mileage: 86k
There was also a few spare parts in the boot when I bought the car. a throttle body, a coil pack, and a maf meter. I can only assume these were used to try and diagnose the issue prior to my ownership

[MoVolvos]

Sorry here’s some more info
Mileage: 86k
There was also a few spare parts in the boot when I bought the car. a throttle body, a coil pack, and a maf meter. I can only assume these were used to try and diagnose the issue prior to my ownership

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If memory serves me right, I had a mild stumbling issue with my 00 S70 SE Base with 150K miles. It started to acted up really, really bad after an engine wash. Before replacing the wire loom I had the cover off and then forgot to replace the oil cap after adding a little oil. Drove home and by the end of the trip the car was smoking. After a good soaping and pressure washing I discovered it was one bad coil and two other coils with hairline cracks. So the mess was a blessing! A set of coils and the car ran fine, well except...

CIP (clean in place) the ETM did the trick for the final smoothing out of the engine and now not a stumble and has been purring. Be sure to use a lint free rag and clean both the front and back of the butterfly as much as possible. Lightly spray the entire ETM and rag and take your time wiping. Don't saturate the pivot of butterfly in case the cleaning fluid gets into the ETM. The pivot however needs to thoroughly cleaned for any gunk binding the movement. Also, be gentle not to bend the butterfly or pivot shaft. The car will stumble from the fumes when you first start back up but will settle in. Hope you get it sorted out!

[MoVolvos]

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Could be a coil intermittently glitching!

In preparing the 2002 V70 XC to potentially replace the 2009 S60 2.5T AWD my Son is still driving, though it was totaled from someone backing into the side and with an insurance estimate of $9K to fix. I removed the newer 00 S70 SE NA coils to swap with the XC70. The S70 hit some black ice so is out of commission with suspension damage but that is another story.

The 02 XC70 was purchased barely starting and then cutting out. The codes led me to troubleshoot and find the Injector under the Charge Pipe to be bad along with the MAP sensor. I replaced all 5 injectors, plugs and the MAP. All went very smooth except for a hiccup / misfire / flare at highway speeds. It really felt like a flare or lower transmission torque mount rather than an ignition issue.

Purchased a kit for the smaller bushing of the Torque Mount and got some Synthetic fluids ready for a drain and fill via extraction. Thought perhaps it just might be the coils so swapped them out first today with the S70. Initially I could only swap out 4 as the S70 is parked at friend's and he didn't have any Torxs for the two Charge Pipe. With only 4 coils replaced the car ran smoother but the hiccup was still there. Got to my parents where I have a second set of tools and changed the coil under the Charge Pipe. Was anticipating and waited for the hiccup / flare on the way home and it never happened. The Injector and Coil that failed in combination were both (#4?) under the Charge Pipe. Perhaps age and more heat exposure caused both to go out though the XC70 is under 84K miles.

Have been driving with that glitch for a few months so thank God for not letting me go down the Rabbit Hole of transmission first, though it could use at least a drain and fill at this time. Have the extractor, fluid and funnel already to go but now can do other more pressing work on the other cars.

According to FCP and other websites the P80 NA parts are interchangeable with P2 Turbos.

5 Pcs Ignition Coils for 2000 Volvo S70 / $74.99 / 3 Year Warranty
https://a-premium.com/product/5x-Igniti ... DZ5wchcJ0B

5 Pcs Fuel Injectors for 2002 Volvo V70 / $50.99
https://a-premium.com/product/5x-Fuel-I ... afzfvznV27

Bosch Automotive 0261230029 Original Equipment Manifold Absolute Pressure (MAP) Sensor for Select Volvo:
1999-04 C70, 2001-03 S40, 2001-02 S60, 1999-00 S70, 1999-02 S80, 2000-04 V40, 1999-02 V70 / $39.96
https://www.amazon.com/Bosch-Original-E ... +Volvo+V70
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[Themapinspector]

Thank you both for your replies. I have previously cleaned the ETM but will do so again (I had this car was lost on the road 7 years ago, with the exact same issues) and replace all 5 coils. Will update with more info on how this goes

[scot850]

As advised above, I also advise to not spray directly into the throttle body with throttle body cleaner. Soak a lint free cloth and use cotton buds if necessary to clean the unit out.

I'm currently working on a P2 02 XC70. 4/5 of the coils have 2 or 3 cracks in the bodies. 1 is a newer replacement. One of the cracked units has a bad coil boot which is hard and crumbled. Strangely it is #4 cylinder! There is also leaking oil in the most of the coil boots and spark plug tubes.

Good Luck!

Neil.