Fjergus
New member
- Joined
- Dec 5, 2014
- Location
- Seattle-ish
Car deets:
1985 240DL wagon with a freshly rebuilt B230F and LH2.2 w/ Chrysler ignition (no EZK yet)
Things I've tried/checked:
The ignition timing is set to roughly 15?, the valve timing is correct, and I've been searching for vacuum leaks for days without finding any. The idle air control valve and throttle position sensor are plugged in to the correct plugs (they are easy to mix up), and the TPS is adjusted correctly. Unplugging the IAC valve causes the idle RPM to drop, so I know it's working properly. Turning the air conditioner knob also raises the idle like it should. The idle speed is roughly correct, too. It starts just fine, and the electrical system works fine whether the car is on or not. The voltage gauge reads a solid 14ish volts with the engine on, the battery appears to be charging, and I am getting no alternator warning lights.
The problem:
The engine is newly rebuilt (a late model B230 from an early-90's car). It runs great at higher RPM's, but it idles like absolute dog****. Rough, wandering idle, the AFR wanders between 13.0 and 16.0 or so (I have an air/fuel ratio gauge), the works. All of the LH2.2 sensors and whatnot were swapped from my old engine, so that's not the issue. It's pretty obvious that I have something hooked up incorrectly, but until yesterday I couldn't figure out what the hell it was.
Yesterday, I think I got a lead. My battery cables are really janky, so I was fiddling with them with the engine running. I accidentally pulled the negative cable off of the battery and... nothing happened. The engine just kept right on running without so much as a hiccup. I played around with it for a bit, but it made no difference whether the battery was plugged in or not. The voltage gauge on the dash doesn't even twitch (it stays at an even 14ish volts).
It appears that the ignition and fuel systems are running directly off of the alternator, and the battery isn't in the loop at all. That would explain why it runs fine at high RPM, but won't idle for ****: the alternator isn't putting out enough juice at idle to run everything correctly when it isn't turning very fast. I'm pretty sure I have a ground in the wrong place somewhere, but I haven't been able to find it yet.
Here are the major engine grounds:
-Alternator ground post to the block through a bolt on the passenger side engine mount bracket.
-Battery ground to the fender through a screw in the ignition coil bracket.
-Battery to the block through a bolt in the driver side engine mount bracket.
...and here are the positive connections:
-Alternator positive to the starter positive terminal.
-Battery positive to the starter positive terminal.
-Battery positive to that goofy terminal block for the fuel injection and whatnot.
Soooo... what the hell am I doing wrong here? Did the wiring loom spontaneously grow another battery somewhere? Do Volvos normally run just fine with the battery disconnected? I don't think I've ever tried it before, honestly. Are there any connections I missed? I'm kind of at a loss here.
TLDR: 240 with LH2.2 and a freshly rebuilt/installed B230F. Very rough idle, and runs whether the battery is plugged in or not. The problem seems to be an incorrectly connected wire and/or incompetence on the part of the installer (namely myself).
1985 240DL wagon with a freshly rebuilt B230F and LH2.2 w/ Chrysler ignition (no EZK yet)
Things I've tried/checked:
The ignition timing is set to roughly 15?, the valve timing is correct, and I've been searching for vacuum leaks for days without finding any. The idle air control valve and throttle position sensor are plugged in to the correct plugs (they are easy to mix up), and the TPS is adjusted correctly. Unplugging the IAC valve causes the idle RPM to drop, so I know it's working properly. Turning the air conditioner knob also raises the idle like it should. The idle speed is roughly correct, too. It starts just fine, and the electrical system works fine whether the car is on or not. The voltage gauge reads a solid 14ish volts with the engine on, the battery appears to be charging, and I am getting no alternator warning lights.
The problem:
The engine is newly rebuilt (a late model B230 from an early-90's car). It runs great at higher RPM's, but it idles like absolute dog****. Rough, wandering idle, the AFR wanders between 13.0 and 16.0 or so (I have an air/fuel ratio gauge), the works. All of the LH2.2 sensors and whatnot were swapped from my old engine, so that's not the issue. It's pretty obvious that I have something hooked up incorrectly, but until yesterday I couldn't figure out what the hell it was.
Yesterday, I think I got a lead. My battery cables are really janky, so I was fiddling with them with the engine running. I accidentally pulled the negative cable off of the battery and... nothing happened. The engine just kept right on running without so much as a hiccup. I played around with it for a bit, but it made no difference whether the battery was plugged in or not. The voltage gauge on the dash doesn't even twitch (it stays at an even 14ish volts).
It appears that the ignition and fuel systems are running directly off of the alternator, and the battery isn't in the loop at all. That would explain why it runs fine at high RPM, but won't idle for ****: the alternator isn't putting out enough juice at idle to run everything correctly when it isn't turning very fast. I'm pretty sure I have a ground in the wrong place somewhere, but I haven't been able to find it yet.
Here are the major engine grounds:
-Alternator ground post to the block through a bolt on the passenger side engine mount bracket.
-Battery ground to the fender through a screw in the ignition coil bracket.
-Battery to the block through a bolt in the driver side engine mount bracket.
...and here are the positive connections:
-Alternator positive to the starter positive terminal.
-Battery positive to the starter positive terminal.
-Battery positive to that goofy terminal block for the fuel injection and whatnot.
Soooo... what the hell am I doing wrong here? Did the wiring loom spontaneously grow another battery somewhere? Do Volvos normally run just fine with the battery disconnected? I don't think I've ever tried it before, honestly. Are there any connections I missed? I'm kind of at a loss here.
TLDR: 240 with LH2.2 and a freshly rebuilt/installed B230F. Very rough idle, and runs whether the battery is plugged in or not. The problem seems to be an incorrectly connected wire and/or incompetence on the part of the installer (namely myself).