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Engine has loss in power upon accelerating after oil change??
This might be a coincidence or related….
I’m working on a 2002 blazer with around 130,000 miles on it
it ran decent open till this point. It needed an oil change pretty badly.
So the filter I used was an AC Delco pf47e
Oil was 10/30 full synthetic super tech
Figured the oil was fine but maybe not lol.
Changed the oil 5 quarts just about. And now I have a noticeable tick in the valve train area. And around town it seems like it’s running on one less cylinder. Idle is pretty low around 500 rpm’s but maybe that’s normal for a vortec 4.3??
I can’t say I’ve ever in my life had a noticeable tick after an oil changed that also resulted in low power. The oil pressure when idling was around 40 psi after warmed up. It’s a noticeable tick now doesn’t seem like a vacuum leak.
Wondering should I run normal Dino oil 5/30 only? Is my ac Delco filter no good?
Im not seeing any codes yet either but maybe it won’t throw one at all.
Update-Just noticed this now
The coil is loose in its case not sure if it’s arcing or not though
Last edited by justblaze83; Jan 1, 2023 at 05:26 PM.
An oil change shouldn't cause any problem. The oil you used is fine. My guess is that you accidentally damaged a spark plug wire or something when you were doing the work. I would examine each one individually, then run the engine in the dark and watch for sparks. Maybe even poke gently at the wires with a stick or something non-conductive while it's running.
Is your check engine light on? That usually happens when there's a misfire, but it may not come on immediately.
Your truck should idle at ~650 rpm. Honestly the best way for DIY diagnostics is to get a scanner. You can get a dongle that plugs into your OBDII port and connects to your phone or tablet via Wi-Fi or BT relatively inexpensively. Others may give more current better suggestions, but I had bought one from BAFX (note they make a different one for Android versus iPhone from I just saw) years ago that you combine with a third party app called Torque Pro. This will help give you real time data so you can see if there is a single cylinder or multiple cylinder misfire.
Your truck should idle at ~650 rpm. Honestly the best way for DIY diagnostics is to get a scanner. You can get a dongle that plugs into your OBDII port and connects to your phone or tablet via Wi-Fi or BT relatively inexpensively. Others may give more current better suggestions, but I had bought one from BAFX (note they make a different one for Android versus iPhone from I just saw) years ago that you combine with a third party app called Torque Pro. This will help give you real time data so you can see if there is a single cylinder or multiple cylinder misfire.
Originally Posted by Tom A
An oil change shouldn't cause any problem. The oil you used is fine. My guess is that you accidentally damaged a spark plug wire or something when you were doing the work. I would examine each one individually, then run the engine in the dark and watch for sparks. Maybe even poke gently at the wires with a stick or something non-conductive while it's running.
Is your check engine light on? That usually happens when there's a misfire, but it may not come on immediately.
I checked it with a code scanner but I got nothing so far. Not sure how long it takes for a light to come on with these things?? I would kill for a CEL
A bum wire plug wire would make more sense than what I’m claiming happened. I’m gonna do more poking around and wasn’t there a trick with a spray bottle of water to find arcs?
A bum wire plug wire would make more sense than what I’m claiming happened. I’m gonna do more poking around and wasn’t there a trick with a spray bottle of water to find arcs?
Yes, but it only tests for cracked insulation. At night and with your underhood light unplugged use a spray bottle set at the finest mist possible and spray all along your wires. If there is a leak you will see tiny flashes of light.
If that doesn't produce any results you can ground each wire using a Philips head screwdriver with a jumper wire wrapped around it and attached on the other end to B- or any good ground on the engine. Disable your fuel pump by pulling the fuel pump relay and have someone crank the engine while you slowly pull the screw driver out of the boot. You should both see a spark and hear a cracking noise. Do this one at a time and don't touch the metal part of the screwdriver or you will get one hell of a jolt. Don't jam the screwdriver into the boot, just set it in there until it's deep enough to near touch the metal part of the wire.
EDIT: I didn't ask, but if you have an incandescent test lamp, you can use that in place of the screwdriver...matter of fact I would use that instead if you have it.
Note this will not check your spark plugs. There are cheap spark testers you can get at the auto parts store that connect between the spark plug and wire.
Yes, but it only tests for cracked insulation. At night and with your underhood light unplugged use a spray bottle set at the finest mist possible and spray all along your wires. If there is a leak you will see tiny flashes of light.
If that doesn't produce any results you can ground each wire using a Philips head screwdriver with a jumper wire wrapped around it and attached on the other end to B- or any good ground on the engine. Disable your fuel pump by pulling the fuel pump relay and have someone crank the engine while you slowly pull the screw driver out of the boot. You should both see a spark and hear a cracking noise. Do this one at a time and don't touch the metal part of the screwdriver or you will get one hell of a jolt. Don't jam the screwdriver into the boot, just set it in there until it's deep enough to near touch the metal part of the wire.
EDIT: I didn't ask, but if you have an incandescent test lamp, you can use that in place of the screwdriver...matter of fact I would use that instead if you have it.
Note this will not check your spark plugs. There are cheap spark testers you can get at the auto parts store that connect between the spark plug and wire.
Lol so I think I got mega lucky, and everybody was right it was a plug arcing after all.
I was poking around earlier today when I happened to notice one of the spark plug boots sticking out a little further than it should’ve been.
it was arcing like crazy. Unfortunately I couldn’t see it because it was deep inside the manifold area.
Either the last person who did plugs on this thing didnt secure it all the way or maybe I somehow pulled it out by accident doing the oil change. Either way I’m not complaining about an easy fix for once.
I appreciate the helpful advice and comments!
This thing sounded just like a lifter tick. It was so loud. And after changing the oil, I could’ve sworn it made sense.
Engine has loss in power upon accelerating after oil change??
