Sputtering/loss of power
02-23-2018, 12:19 AM
#21
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I told you above where to start. I'm going to look into my crystal ball and bet you have some type of fuel system problem. Maybe rust or water in the injector screens or worse. Have it scanned while driving and watch the fuel trims and o2s while its sputtering. Data is your friend.
so turns out I have a cracked valve spring. I have purchased the 660 dual valve spring kit, would you recommend replacing just the one spring or all springs?
02-23-2018, 12:21 AM
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One of the knock sensors failed on my '00 car, and it didn't cause any driveability issues at all - just an SES light. But, I guess there could be more than one failure mode for this.
I don't see how that light could be flashing without a code present for misfires, unless the scanner is bad, or you somehow cleared the MIL prior to reading the codes, or some sort of modification was performed to misfire reports in the tune. When the SES light isn't flashing, does it just stay on solid or does it not show up at all?
I don't see how that light could be flashing without a code present for misfires, unless the scanner is bad, or you somehow cleared the MIL prior to reading the codes, or some sort of modification was performed to misfire reports in the tune. When the SES light isn't flashing, does it just stay on solid or does it not show up at all?
so turns out I have a cracked valve spring. I have purchased the 660 dual valve spring kit for my PRC heads. would you recommend replacing just the one spring or all springs?
02-24-2018, 09:41 PM
#23
I'm not a spring expert by any means but its cool you found the issue. Giving advice over the net is a crap shoot at best. I'm sure someone will join in with spring advice but I'll tell you this much If you want springs to last always warm up the engine good before running it hard. Cold springs break easy, I have a simple 3-5 minute rule before I move my cars and I won't run them hard until they up to full temp.
Last edited by RockinWs6; 02-24-2018 at 09:46 PM.
02-25-2018, 08:04 AM
#24
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One of the knock sensors failed on my '00 car, and it didn't cause any driveability issues at all - just an SES light. But, I guess there could be more than one failure mode for this.
I don't see how that light could be flashing without a code present for misfires, unless the scanner is bad, or you somehow cleared the MIL prior to reading the codes, or some sort of modification was performed to misfire reports in the tune. When the SES light isn't flashing, does it just stay on solid or does it not show up at all?
I don't see how that light could be flashing without a code present for misfires, unless the scanner is bad, or you somehow cleared the MIL prior to reading the codes, or some sort of modification was performed to misfire reports in the tune. When the SES light isn't flashing, does it just stay on solid or does it not show up at all?
02-25-2018, 02:03 PM
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In my case, there was no actual knock, just a failed sensor. It caused no driveability issues, just a code for the sensor.
PCM timing retard (i.e. low octane spark table) by itself won't cause a misfire that leads to any hesitation, just reduced power.
Any misfires that lead to a flashing SES light should in fact set a code, unless perhaps the tune has been messed with.
To the OP: Not sure what type of valve springs you have now or how old they are, but if you're going with a different spring then I'd change them all. If it's the same spring and one has failed, then perhaps they are old and all in need of replacement. If they are fresh and one has failed, then you may have a bad batch or springs not well matched to the combo. So there are several possibilities here.