[TravisHenderson]

I bought a 2007 159 2.2 JTS in November of 2021. 203,000km on the clock and not in the best cosmetic shape, but seemingly mechanically sound, and it's run well since the first test drive. The only persistent issues I've had are an unpleasant smell of fuel at the back right wheel, and that it often won't start on the first try of the day (just chugs out at the end of the startup sequence), but it always roars to life on the second try and then starts fine for the rest of the day. MultiECUscan told me the intake valve timing solenoid was dead when I bought it, so I replaced both the intake and exhaust; I got a bit of misfiring on the first couple of starts after doing that but it seems to have worked itself out since.

Two days ago I drove it about 50km round trip, from stop start traffic to 100km/h on the highway, and it went like a champ. Fast forward to today, when five minutes from home the Check Engine Light started flashing and I had to put my foot right to the floor to make it up a hill I can usually cruise up effortlessly in fourth gear. I turned around immediately. Downhill and level driving were fine, but it gave me trouble going up every hill on the way back, misfiring terribly, jerking, flashing the light, making me feel like I was going to have to push it home. I slapped MultiECUscan on it as soon as I got home and the diagnosis is:

P0300 - Ignition Failures (generic)
P0303 - Cylinder 3 ignition failures
P1670 - Fuel Pressure
P0301 - Cylinder 1 ignition failures
P0304 - Cylinder 4 ignition failures

There's also a lot of fuel leaking down the right side of the tank, just ahead of the back right wheel. I wrestled the back seat out and found a crack in the plastic top of the pump assembly housing, so obviously I'll take care of this ASAP. I'm going to try to patch it with some JB MarineWeld in situ first (high pressure, fuel-resistant, works on plastic, worth a shot) but I suppose I'll get a new pump unit if that doesn't work.

Does anyone have any experience with the P1670 code, though, or misfires going uphill? I've searched the forum and seen the high-pressure fuel pump and fuel injectors mentioned, which has my stomach in knots, but nobody's symptoms seem to match mine exactly. Any advice would be appreciated.

 

[TravisHenderson]

Quick update: I pulled the pump/sender unit out of the tank and inspected it a bit more closely. The one major crack was obvious, but I found hairline cracks all around the elbow leading to the output pipe, to the point where I suspect the plastic was essentially porous and was just letting fuel out pretty freely:

I had a go at plastic welding first thing. Using a 30W soldering iron with a standard pointed tip I just melted a channel along each crack as deep as I dared, then 'swept' molten plastic back into the channel to fill and seal it up again. I cut a piece of donor plastic out of the circular turret piece at the top of the pump assembly and used this as a welding stick to get some more fresh material into the area and thicken it up. Not the prettiest end result but I felt pretty confident that I'd achieved a good seal at the end:

Next up I roughed up and cleaned the area with isopropyl alcohol and then covered it in JB Weld 8272 MarineWeld. This stuff is a 24 hour cure epoxy, which in my mind says it's going to be more durable than the shorter cure time products (no idea if there's any truth to that, but it makes me feel better). It cures rock hard, shiny and smooth, promising to be fuel resistant and waterproof to 5020PSI, and I was pretty happy with how it turned out:

Just to be safe I waited the full 24 hours and then roughed it up, cleaned with alcohol and applied a second coat of the stuff, covering the entire first coat and extending out a little further. And then I did a third coat 24 hours later. Frankly, if this doesn't hold then nothing will, and I'll just have to buy a new pump unit anyway, so why not? Anyway, back in the car:

I watched the pump like a hawk as I reconnected the battery and put the key in - no signs of a leak. I started the engine - no leak. I revved it in the driveway for a while - no leak. I went for a drive, hyper aware for any faltering or misfiring, and honestly it feels pretty good. Drove up the most daunting hills my suburb has to offer and the car was fine. I got home and checked the pump again and was delighted to find it was bone dry. MultiECUscan gives a clean bill of health, no misfires, no P1670.

Of course the big question is whether this repair holds up longterm, but only time will tell. I'll leave the back seat unfastened for the next little while and keep checking the pump before and after every drive, but for now it's looking OK.