IPD sale XeMODeX - Experts in Volvo Electronics
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy your stuff using this and it helps MVS!

'98 V70 T5 won't start, P0301 & P0304

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

dmechnic
Posts: 13
Joined: Mon Dec 30, 2019 5:20 pm
Year and Model: 2004 V70 R
Location: Chicago
Has thanked: 3 times
Been thanked: 0
United States of America
dmechnic

'98 V70 T5 won't start, P0301 & P0304

Post by dmechnic » Tue Jan 07, 2020 5:06 pm

This may be a bit long so I apologize in advance. My daughter's '98 V70 T5 with +200k miles died while she was driving to work. I went and tried to get it running and it refused to start, only cough & half attempts at running. Called roadside & sent her on her way and waited. My cheap OBD reader did not pull up any codes. A guy who I thought was roadside cause he had strobes on the front of the truck (it was dark) stopped and asked what the problem was. He said maybe the fuel pump, so turn the key and give a listen. Tried it and pump made some noise so we figured give it go. Rough start but idle smoothed out. Car had been sitting off for maybe 10-15 minutes before that. He left, real roadside showed up and followed me home. When stopping the idle was really rough and under more aggressive acceleration it was flat, like the turbo was dead, but it still ran and slowly rev'd up. Got it home, talked with a family member who works as a mechanic and he thought maybe a cam or crank sensor. While waiting for those to arrive I came out here and found rough idle coming to a stop could be fuel pump or MAF. Parts show up, take out intake/filter box, turbo output tube, and disconnect distributor wires so I can get to the two sensors. Also find and replace a broken 90 degree vacuum fitting that attaches to the back of what I think is a regulator of sorts on the turbo (I'm not well versed on all the bits).

With the new sensors in and everything hooked back up I give it a go. Starts just fine but when I shift into reverse it bogged down, sputtered while a rough idle but didn't die. I take it for a quick run around the block, acceleration is better and seems to be ok except for when I come to a stop...back to the rough idle/sputtering but not dying. While in park quick stabs at the accelerator cause it to lag/sputter for just a tiny bit and then revs right up nice and smooth. Get it back in the garage and do some more reading online. Seems the fuel relay is a bugger so I make a jumper and give it try. Idle seemed a little better but not resolved (not surprised as a relay should just either be good or dead, no?). One thing I did note was that with the relay jumper in place the idle did not drop down from 1K to 600-700 when put into gear. The CEL had managed to stay off for a portion of the test driving but eventually came on (flash then solid) when my mashing of the pedal made it bog down and cough. My OBD reader again did not pull up any codes. I put the relay back in and started it up and when put into gear it starts to sputter again and this time dies. Family mechanic say "fuel pump" and the forums seem to agree so I replace the pump. Nope, still won't start. Coughs, tries to catch but fails. I borrow a different OBD reader and am able to get P0301 & P0304 out of it. I know these well from my two 2004's (C70 T5 & V70 R, yeah I love it) but those have the independent coils, this old school distributor and single coil is a different beast for me, though I'm old enough to be familiar with the basics. Getting a better OBD reader so I can get more thorough codes is an obvious issue. Besides that, what do you think I should be looking to do? I cannot believe it would run as well as it did (while it did) had I put the plug wires back on incorrectly. Bad coil? Old wires that gave it up after being moved a bit? Kinda lost at this point. Thanks in advance for any help.

polskamafia mjl
Posts: 2626
Joined: Wed Apr 01, 2009 1:10 am
Year and Model: 1995 Volvo 854 T-5R
Location: Hershey, PA
Has thanked: 6 times
Been thanked: 6 times
Poland
polskamafia mjl

Re: '98 V70 T5 won't start, P0301 & P0304

Post by polskamafia mjl » Tue Jan 07, 2020 10:58 pm

Here are two links to get you started since I'm not too familiar with these codes:

viewtopic.php?t=68705

https://www.youtube.com/watch?v=Sg7iFytxfzQ

You are correct that the fuel pump relay will either work or it won't, it's not going to kind of work. I think the same is true for the fuel pump.
'All my money is gone and I have an old Volvo.' - Bamse's Turbo Underpants

Current: 1995 Volvo 850 T-5R Manual - Bringing it back from the brink of death
Previous: 1996 Volvo 850 GLT - Totaled

User avatar
abscate
MVS Moderator
Posts: 19695
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 248 times
Been thanked: 807 times
Trinidad & Tobago
abscate

Re: '98 V70 T5 won't start, P0301 & P0304

Post by abscate » Wed Jan 08, 2020 1:50 am

There are only two people on this forum who can probably diagnose a poor running problem when they sit in front of a car. The rest of us, self included, have to diagnose

We can skip compression for the moment as we seem to have decent power at higher rpm, so major mechanical stuff can be ruled out.

Measure fuel pressure at rail. Confirm you have correct operating pressure.

Evaluate ignition. Remove and inspect plugs, cap, rotor. They need to be clean and shiny and Bosch parts. Reinstall and ground a removed plug to the block and look for a nice fat blue spark.

Remove and inspect all the turbo induction hoses from turbo to throttle body. A cracked hose here will cause poor performance at low speed which will improve at higher rpm. A split intercooler will also do that but usually has to be found by smoke test
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW
Link to Maintenance record thread
Link To Volvo Glossary

Chuck W
Posts: 238
Joined: Wed Dec 24, 2014 10:45 am
Year and Model: 97 854 T5
Location: Indianapolis, IN
Has thanked: 16 times
Been thanked: 32 times
United States of America
Chuck W

Re: '98 V70 T5 won't start, P0301 & P0304

Post by Chuck W » Wed Jan 08, 2020 7:35 am

Pull the dist cap and check the cap/rotor. While you're in there, make sure the cam seal isn't leaking/seeping oil all over the place.

If they're old and dry and the PCV system isn't up to snuff, a boosted run could push oil past them, or push the seal out of place. Oil inside the cap would cause issues.

It's also possible that you have a dodgy injector or two (bad batch of gas?)

redc70
Posts: 81
Joined: Wed Dec 28, 2016 11:20 am
Year and Model: 1999 c70 convertible
Location: Texas
Has thanked: 3 times
Been thanked: 2 times
United States of America
redc70

Re: '98 V70 T5 won't start, P0301 & P0304

Post by redc70 » Wed Jan 08, 2020 8:01 am

For what it's worth, P301 and 304 are cylinders 1 and 4 misfires. I'd check the plugs and wires to those cylinders, could also be the injectors on those cylinders. Just went through this with my Nissan Armada. But it was code p0300, random multiple misfires. Tracked it down to injectors, after coils plugs maf, etc. At least you now know which cylinders are giving issues.

User avatar
abscate
MVS Moderator
Posts: 19695
Joined: Sun Feb 17, 2013 5:54 pm
Year and Model: 99T5 ,99S70,2005V70
Location: NYC, ALBANY NY
Has thanked: 248 times
Been thanked: 807 times
Trinidad & Tobago
abscate

Re: '98 V70 T5 won't start, P0301 & P0304

Post by abscate » Wed Jan 08, 2020 11:06 am

If it is running really badly at idle, the misfire codes arent registered well to the cylinders in question - so don't bank on cylinders having a problem quite yet.
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 BMW
Link to Maintenance record thread
Link To Volvo Glossary

redc70
Posts: 81
Joined: Wed Dec 28, 2016 11:20 am
Year and Model: 1999 c70 convertible
Location: Texas
Has thanked: 3 times
Been thanked: 2 times
United States of America
redc70

Re: '98 V70 T5 won't start, P0301 & P0304

Post by redc70 » Wed Jan 08, 2020 11:23 am

I agree on not the cylinders themselves, but whenever there is a misfire code on a particular cylinder, the ecu is telling us it has a some kind of problem with that cylinder, whether spark, fuel or whatever. So in my humble opinion I would start there and look at plugs first, then wires then possibly injectors then backtrack from there to fuel relay, fuel pressure etc...
In the case of my Armada, it ran really rough at idle, but was smooth under acceleration and cruising. Not saying it is injectors here, (or anything else), but at least the ecu is telling is what direction to look in first.

User avatar
RickHaleParker
Posts: 3437
Joined: Mon May 25, 2015 2:30 pm
Year and Model: See Signature below.
Location: Kansas
Has thanked: 3 times
Been thanked: 411 times
United States of America
RickHaleParker

Re: '98 V70 T5 won't start, P0301 & P0304

Post by RickHaleParker » Wed Jan 08, 2020 12:25 pm

Wait until nightfall or put the car in a dark garage. Open the hood, start the engine and look for leakage in the spark plug wires and distributor cap.
Platform: P80 1998 C70, B5234T3, 16T, AW50-42, Bosch Motronic 4.4, Special Edition package, Plant: Uddevalla Sweden.

Platform: X40 (Nedcar) 2003 S40, B4204T3, 14T twin scroll AW55-50/51SN, Siemens EMS 2000. Plant: Born Netherlands.

Platform P2 2005 XC90 T6 Executive, B6294T, 4T65 AWD, Bosch Motronic 7.0,
Plant Torslanda Sweden.
----------------------------------------------------------------
1997 S90, B6304S, AW30-42, Bosch Motronic 4.4 - Sold

dmechnic
Posts: 13
Joined: Mon Dec 30, 2019 5:20 pm
Year and Model: 2004 V70 R
Location: Chicago
Has thanked: 3 times
Been thanked: 0
United States of America
dmechnic

Re: '98 V70 T5 won't start, P0301 & P0304

Post by dmechnic » Wed Jan 08, 2020 3:38 pm

When I crank it over it sounds like its trying but then there is one where it sounds like it is fighting itself, like an ignition out of sequence that stops the crank for moment. I pulled the plug wires and had some standing oil in #2 plug well that likely leaked in as the plug wire seat was not secure (some standing oil in some of the crevasses of the head too...for some reason there is red RTV around the neck of the oil filler too...ultimately thinking possible PCV issue as oil source as the oil is only near the black tube that is just left and behind the oil fill). Anyway, pulled plug #1 and tried cranking and got spark...but I also got a fireball out of the open cylinder. That has me a bit puzzled as there was no ignition source available. Possible "backfire" through one of the manifolds that allowed it to reach that cylinder and ignite the mix?? IDK. Checked all the plugs, none loose or damaged. Pulled the distributor cap...trace oil inside but only on the bottom, not saturated and rotor assembly is clean. There was trace amounts of red RTV on the lip of the shroud that seats against the head and has the o-ring that seals on the actual distributor cap. Double checked before disassembly and plug wires were connected correctly, not surprising as it did run before giving it up. Right now I'd be thrilled just to get it running, crappy idle or not.

hipcheck
Posts: 4
Joined: Tue Oct 15, 2019 7:34 pm
Year and Model: 1997 850
Location: Arkansas
Has thanked: 0
Been thanked: 0
United States of America
hipcheck

Re: '98 V70 T5 won't start, P0301 & P0304

Post by hipcheck » Wed Jan 08, 2020 7:28 pm

Have someone crank and start the car while armed with some carb/fuel injector cleaner spray. Provide small sprays around your intake manifold to engine block junction/ throttle body to intake manifold junction/ TPS sensor and the rod it moves/ each injector hole/ the big vacuum lines near the vacuum tree/base of vacuum tree/ PCV hose on left side of manifold/ fuel line from injectors to vacuum tree. Eventually you should hear the engine rev higher and a few small sprays should get it to idle for longer amount of time. Start looking where this leads you. I did my PVC system and mounted the intake manifold back with the metal clip that holds the vacuum line in place (near throttle body) under the intake manifold. No start, no idle, etc. checked fuel pressure, spark plugs, gap, crank sensor, EVERYTHING.



If it isn’t running and having multiple misfires check for vacuum leaks.

Steve

Post Reply
  • Similar Topics
    Replies
    Views
    Last post