Hi guys. Just after some help with narrowing down a problem with my ecotec....I have been racking my brain trying to figure it out, it has only presented itself over the past week or so. Symptoms, idles and drives rough (car sounds lumpy but I only have stock cam ), it also feels like its hesitating...only a little bit but its still noticable, I have to go around 40% throttle to get to 60 quickly at the lights where as I used to only have to tap the throttle to get up there and when I take my foot off the throttle the engine feels like its heavily engine braking without any real need (that almost feels like the engine is being choked) When idling the exhaust is a solid note but occasionally dips every few seconds (almost sounds like a misfire, but it doesn't always happen at the same time, its very random) (also seems to have been smoking a bit as the tail pipe has gotten really black the last few days) I have checked all filters, MAF sensor, throttle body, reset ECU, error checked. Plugs and leads are only around 2000km old and upon inspection the plugs look ok. I thought it may have been a bad batch of fuel but I went to a different servo and filled up and same deal. The only thing I can think of is maybe O2 sensors or injectors (both of which aren't cheap). Anyone got any suggestions? Engine is fairly stock apart from Mace Memcal, Manifold Spacer and CAI, Pacemakers through to high flow cat and 2.5" system.
You said you checked the error codes, if it was o2 sensors it should bring something up. What happens when you plant your foot? Does it sound like it misses, surges slowly up to speed?
Yeah, didn't get any errors, I have seen 02 sensors fail without showing a code on the rare occurence in the past though. When I plant my foot it still takes off like it used to (really torquey) but it hesitates for around 2-3 seconds before it does this and if I am cruising and want to kick it down a gear I used to just lightly apply pressure to the throttle and it would take off like a mad thing, now I have to go to about half thottle before it hesitates and drops back a gear It doesn't really seem to sound like its missing but it does sound quite rough and lumpy People driving behind me have said that when I plant it they can see it hesitate then when it finally picks up it dumps a fair bit of black smoke.
Dirty fuel injectors will make it run crook, if most other parts have been replaced and have made it run no better ,then thats where Id look, especially if the car has done over 100,000 km or more on the old injectors. I didnt want to spend $500 or more on brand new bosch injetcors, and I didnt want remanufactured ones, even after being rebuilt, they never flow as good as when they were brand new. So I bought and fitted these brand new "cheapie" fuel injectors, (shown in the link below) to my VS ecotec after it wasnt getting the best fuel economy, it wasnt running properly and I just couldnt seem to get it to run at its best, and Id just about replaced everything else except the injectors. I found these injectors, the same as the ones in the link below, on ebay, so I thought Id give them a go to see how they went, they arent a great deal to buy, and theyre brand new, not just "cleaned" or "reconditioned" or "remanufactured" etc, and so far, (6 months so far) theyve been running excellent, the car runs noticably better than before, starts instantly, a lot better on fuel now. The guy who sells these got them to me in 2 days by post and they came fitted with new o-rings too, ready to install. I really didnt know what these would run like being cheapies, and not bosch etc, but theyve been excellent so far. If I can get 100,000 km from them, I will be happy with that, especially with the fuel economy I get at the moment, I will buy more the same and fit them again after that if they last that long.. My engine is fairy standard except for the usual V6 mods, headers,exhaust,tune etc. ---COMMODORE NEW FUEL INJECTORS VN - VY 6 CYL ALL MODELS | eBay---
