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Hi,
I wanted to set my idle mix on my 1984 Recaro. The dwell meter is not showing anything. My mixture solenoid is also not tapping when ignition is on. Resitance on the solenoid is always the same on all of my 3 carburetors (got 2 spare), so I guess they're not all broken. I tested both cables from the plug, all the way to the ECU, no breaks, pins aren't corroded either. Got 12v on the pnk/blk when hot and 4.8v on the lt blu. (Engine not running). Carb is new refurbished. Got very rough idle, bad cold start.
Of course it could. Not likely at all, but not impossible either. It certainly would not be an automatic jump-to conclusion however.
Does the Check Engine light come on with the key on and engine not running? Does it go out when the engine is started? If it doesn't come on, that's the first thing I'd fix. Change the bulb most likely. (note the heavy emphasis I place on the concept of "likely" and the difference between that and "possible") The bulb is driven by a lamp driver, which is a little greenish plastic box hanging kind of under the radio in the console area, about the size of a deck of playing cards. Its logic is, it turns the light on by default, and the ECM turns the light off when its program tells it to. If the ECM is completely dead, or even totally disconnected, the light will be permanently on.
If the light works, check for codes, with the key on and the engine not running. You should get a code 12 if nothing else. If you get no codes at all, then the ECM is not commanding the lamp driver, for whatever reason; and then, it might be suspect. So, get the light working, and check for codes, and go from there.
The ECM has very little "authority" over the carb. The carb mostly takes care of fuel metering all on its own. The ECM only trims it a little bit around the edges. Neither a "rough idle" nor "bad cold start" can be blamed on it; most especially NOT a cold start problem. That's a choke problem.
One thing at a time though. Start with the Check Engine light as described.
Last edited by sofakingdom; Yesterday at 09:33 AM.
Of course it could. Not likely at all, but not impossible either. It certainly would not be an automatic jump-to conclusion however.
Does the Check Engine light come on with the key on and engine not running? Does it go out when the engine is started? If it doesn't come on, that's the first thing I'd fix. Change the bulb most likely. (note the heavy emphasis I place on the concept of "likely" and the difference between that and "possible") The bulb is driven by a lamp driver, which is a little greenish plastic box hanging kind of under the radio in the console area, about the size of a deck of playing cards. Its logic is, it turns the light on by default, and the ECM turns the light off when its program tells it to. If the ECM is completely dead, or even totally disconnected, the light will be permanently on.
If the light works, check for codes, with the key on and the engine not running. You should get a code 12 if nothing else. If you get no codes at all, then the ECM is not commanding the lamp driver, for whatever reason; and then, it might be suspect. So, get the light working, and check for codes, and go from there.
The ECM has very little "authority" over the carb. The carb mostly takes care of fuel metering all on its own. The ECM only trims it a little bit around the edges. Neither a "rough idle" nor "bad cold start" can be blamed on it; most especially NOT a cold start problem. That's a choke problem.
One thing at a time though. Start with the Check Engine light as described.
Hi,
Check Engine is on, got Code 54. (Sorry, forgot to mention that).
The voltage on the blue wire should be only either 12V or ground at any given moment. It should switch back & forth about 7 - 10 times a second. The solenoid pulls in when that wire goes to ground. It might "look like" some intermediate value on a DC meter, because it's only energized part of the time. 4.8V in that case would correspond to a duty cycle of about 40% which is highly believable in a general way. Not sure why you're not hearing it click.
There's a bright green connector over near the blower motor that's also on that wire, so you don't have to back-probe the one on the carb.
If it flashes codes, the ECM is most likely OK. Again, no guarantees, butt that VASTLY improves the odds that it's OK. It's possible for one driver to be bad and the rest of it still be good, butt those drivers are pretty robust, and rarely fail. Not "never", just, "rarely". Again, not the jump-to conclusion before everything else that's MORE likely has been ruled out.
Code 54 makes no sense. Doesn't apply to carbed cars. Are you sure it's not 45? Reset the ECM by disconnecting the batt cable for 5 minutes or so, and see if the light goes out at least for a little while, then if it comes back on, read it again.
Last edited by sofakingdom; Yesterday at 11:14 AM.
