Wednesday, February 17, 2010 - 11:33 pm, by: Frank Csapo(264ttr)
I've been having a problem with my car having a bad hesitation when the car is cold/warming up, but goes away once the car is at operating temperature. If I push the throttle about 1/3-1/2 of the way down and keep it there, the revs will build and when boost is about to come on, it will stutter and jerk as if it's missing, but I don't think it actually is missing. Keeping the throttle in the same position, eventually at around 3000rpm boost will come on as per normal. It almost feels like something is stuck closed and eventually opens allowing full power. This will continue until I get to operating temperature. This hasn't been a sudden problem either, something that's gotten slowly worse over the last 6 months.
I am also getting steadily worse fuel economy. When I first finished my engine conversion I was getting about 300km to a tank, now I'm down to 200km, sometimes even as bad as 180km per tank.
Thursday, February 18, 2010 - 12:14 pm, by: Aaron Casey(Blownminiturbo)
try a new fuel filter and get the injectors tested. i had a hesitation like this was injector occasionally not firing. also check your plugs and coil packs. for oil around them and also general condition.
Thursday, February 18, 2010 - 09:31 pm, by: Rob Rojo(Rob_tt)
My old car used to misfire exactly as you described when cold which turned out to be just the plugs.
The fuel economy your quoting sounds like there is something else wrong for sure. 180k's to 50L (assuming the volvo tank is 60 and not running it empty) is 27.7L/100klm would be the worst economy I have ever heard of in a 1JZ powered car.
I would be swapping the O2 sensor first and see if that makes a difference as it is a quick and easy job, if that doesn't improve the economy then try another map sensor and then the ECU which is expensive but leaky capacitors are known to cause bad economy.
Are you still running stock injectors and ECU?
Frank Csapo Tinkerer NSW Volvo 244GLE with 1JZ-GTE
Thursday, February 18, 2010 - 10:40 pm, by: Frank Csapo(264ttr)
I'm thinking I'll be giving the car a bit of a service to cover all bases. I'll check the plugs and change if necessary, and I know some guys who can give my injectors an ultrasonic clean.
I have a 55L tank, but when the needle reads empty there's still 10L to go, as I only ever fill up 45L. Either way, the economy is terrible. I'll see if I can get my hands on another O2 sensor, but I don't have any soarer spares lying around.
And yes, I am still running stock injectors and an A/T ECU, as my donor car was automatic, but I run the R154.
Friday, February 19, 2010 - 07:06 pm, by: Boris Siljanoski(Z2tt)
Think of it like the catalyst in Cat converters that depletes over time, it's similar to why o2 sensors fail. Other reasons why they fail is if coolant gets into the combustion chamber.
Non heated sensors usually last 50,000km, where heated sensors last about 100,000km to 150,000km.
Friday, February 19, 2010 - 07:13 pm, by: Rob Rojo(Rob_tt)
Doesn't make a whole lot of sense when I have seen plenty of soarers with well over 200000k's with working original O2 sensors and it was working properly before I removed it but anyway if you can pick a new one up for $40.00 then that sounds like the way to go.
Thursday, February 25, 2010 - 10:35 pm, by: Frank Csapo(264ttr)
Hey sorry for the late reply guys, thanks for the offer Rob but as Boris said, new ones can be had for cheap so I might go that route. Might just change it as a precautionary measure, though I hope it helps the issue because I filled up yesterday and that tank only got me 194km.
Thursday, February 25, 2010 - 10:58 pm, by: Boris Siljanoski(Z2tt)
If your only getting 200km or so on a full tank there must be something seriously wrong. Isn't the tank about 70 or 80L? Then your fuel economy is around 40L/100km
Friday, February 26, 2010 - 12:00 am, by: Walter Gillmore(Cl33pa)
wow have you checked your fuel lines mate? i dont think an engine can ingest that much fuel without going into hydrolock!! a tiny pinhole in your fuel lines would suggest the bad fuel economy and the hesitation as your not gettin good fuel pressure to the injectors. have you tested the fuel pressure in your fuel rail?
Friday, February 26, 2010 - 11:04 am, by: Frank Csapo(264ttr)
The tank is 55L, but when the needle reads empty there is still usually 10L left. So when I fill up, 45L goes in, which translates to around 23L/100km.
I gave my fuel lines a visual check and I can't see anything amiss. There's no fuel smell to indicate leaking fuel, no thick black smoke out the exhaust to indicate it's running too rich. Other than the hesitation, the car runs well. I will see a mechanic mate of mine hopefully next week who can test the fuel pressure for me.
Monday, March 01, 2010 - 12:09 am, by: Frank Csapo(264ttr)
I pulled out the plugs yesterday and they were all fouled up and black, so this is probably what's causing the miss. But I still need to find the reason as to why they are fouling up. The plugs are NGK Iridium, which are supposed to last for 100,000km, these have probably done 15,000. Bought new plugs today, but will only install them once I find out the main cause.
The coil packs themselves were in good condition with no visible damage or cracks. There was however some oil around the coil packs, but this is probably from when I had the cam cover gaskets changed a few months ago.
I also checked that the MAP sensor was working correctly, disconnecting it caused the engine to nearly stall and run super rich, reconnecting it made everything OK again.
Boris, concerning your list of things to check: Temperature sensor and thermostat are relatively new, and are in good working order. Fuel filter is 3 years old, and I will be replacing it next weekend. Air filter is a K&N which I cleaned about 2 months ago. Plugs are to be installed on the weekend. Injectors I will clean if new plugs doesn't resolve the misfire.
As for the O2 sensor, I want to extract some error codes from the ECU to see if it's coming up as a problem, but am wondering what's the best way to do this since I don't have an original Soarer dash to display the codes, nor do I have a check engine light to flash the codes to me.
Frank Csapo Tinkerer NSW Volvo 244GLE with 1JZ-GTE
Sunday, March 14, 2010 - 09:42 pm, by: Frank Csapo(264ttr)
An update on this issue, I haven't had a chance to replace the plugs and fuel filter yet (busy weekends lately), but I did pull the ECU out to inspect it internally for leaking caps etc. Whilst all the capacitors seemed to be okay, no bloating or obvious signs of leaking, I did notice something unusual. I mount my ECU vertically in the passenger footwell, with the plugs at the top, and inside one of the plug sockets there was an abundance of what looked like oil. Now it can't be blown caps because it means the leakage would have had to travel against gravity, and there's nothing above the ECU that could drip onto it, and the wiring harness was clean so nothing worked it's way along the harness towards the socket. The amount of oily substance was enough to short almost all the pins together, so I'm thinking that this may be a contributor to my issues. Does anyone have any ideas for an explanation for this?
Monday, March 15, 2010 - 09:49 pm, by: Frank Csapo(264ttr)
I will. I was also considering replacing the caps anyway, as a precautionary measure, as I've read they can dry out without looking like they're damaged. I know a good electrician with steady hands who could do the work for me, so I will run it by him tomorrow.
Tuesday, March 16, 2010 - 10:46 am, by: James Wilson(Ser493)
My plugs on my ecu are identical. I am having misfire issues on number 6 cylinder and have now purchased another ecu. I soaked my plugs in degreaser and then sprayed all contacts with CO Contact cleaner. Now they are nice and clean. I would say it's probably supposed to be there but it does look very sus. It would be interesting to find out if it's supposed to be there or not. Any ideas any one? My theory was that the oil had traveled through the loom??
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