by "DC3 LS, will be perpetually replacing cars until the end of time" (dc3ls-)
Published 11/01/2017 at 13:51
by "DC3 LS, will be perpetually replacing cars until the end of time" (dc3ls-)
Published 11/01/2017 at 13:51
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So it’s an 89 Galant that’s misfiring. My question is, is the fuel system on these hard to diagnosis? I’ve heard a lot of these early fuel injection systems were a pain in the ass, but I don’t have much experience with pre 90's FI.
The owner thinks it’s a HG, but I don’t really know how that’d cause a misfire. I’d think it would be an ignition or fuel issue. Or even a bad exhaust/vacuum leak.
"crowmolly" (crowmolly)
11/01/2017 at 13:57, STARS: 5
Before doing a single thing with the EFI system I’d start with the triforce of neglect :
Spark plugs
Fuel filter
Air filter
My money is on the plugs being off/dirty.
Edit: CL says “has new cap/rotor and plugs”. Start there IMO. Somebody may have done something as simple as not checking plug gap.
"CalzoneGolem" (calzonegolem)
11/01/2017 at 13:57, STARS: 1
Too much coolant in the cylinder causes the gas to not ignite / ignite poorly.
"DC3 LS, will be perpetually replacing cars until the end of time" (dc3ls-)
11/01/2017 at 13:59, STARS: 0
He did say it’s not loosing coolant. Plus I’d imagine just watching the exhaust when it does it would confirm or deny that.
"CalzoneGolem" (calzonegolem)
11/01/2017 at 14:01, STARS: 0
Yeah I mean that’s just an explanation of how a bad HG could cause a misfire.
"I hoon, therefore I am" (hookemdevils22)
11/01/2017 at 14:11, STARS: 1
Man, that thing is clean. Here’s what I would do:
Compression test, and preferably a leakdown test
Fuel pressure test at idle and under load (you can rent a gauge and run it outside the hood).
Inspect plug wires. It says new cap/rotor and plugs, but I’d ask for receipts.
Visually inspect vacuum lines for cracks.
"AMGtech - now with more recalls!" (amgtech)
11/01/2017 at 15:18, STARS: 1
Could also cause low compression, low enough to misfire. It also doesn’t take much coolant to extinguish a spark, not necessarily enough to notice coolant loss.
"DC3 LS, will be perpetually replacing cars until the end of time" (dc3ls-)
11/01/2017 at 15:31, STARS: 0
Yeah, If I wind up checking it out I’ll make sure to get a compression/leakdown test on it.
"Die-Trying" (die-trying)
11/01/2017 at 15:56, STARS: 1
NOOO, not always enough to watch the exhaust...... get a dye tester. those are worth their weight in something valuable. you can find a head gasket on its way out with it when nothing else gives any indication
also......... HOLD OUT FOR ANOTHER INTEGRA