Alternater problem??? Please help.

[airhead04]

Well the other day i went to start my car up and let it warm up. I went outside started up the car (takes about 5 seconds to start, my starter is blah. and yes i have another one to put on and yes i know about the relay mod. so dont post about that please.). The car started and I went back inside. I came out and hopped in and the car was about half way to op temp. So I turned my head lights on, and turned on my heat to high. And the car died. Started right back up fine, it just bothered me that it shut off.

So on to yesterday, I was cruising in 3rd gear when a car pulled out in front of me. So I pushed my clutch in and the car hit real low rpms...like 400ish. So I tried to see if it would repeat it. And sure enough it did, except this time it shut off. It does it every now and then but not often.

I was told it may be my alternator. But Im not sure, I havent tested it yet.

The CEL light came on when the car shut off. But no codes were recorded. :dunno:

I just want to fix this. So any help is appreciated.

Btw its been dropping into the single digits here, idk if that will affect anyones answers or not. Thanks guys

-David

 

[jetjock]

I doubt it's the alternator. Does the battery light come on? At least see what voltage is being delivered to the battery.

As for the MIL don't worry about it. The ECU does a bulb check whenever rpm falls below 400...

 

[airhead04]

Battery light comes on when the car dies, yes. Ill check the voltage tomorrow.

I was told it could be the regulator in the alternator. Any ideas on that jetjock?

 

[jetjock]

Well, the battery light is going to come on when the engine dies. The alt isn't working for sure then. If it's off when the engine is running the alt is probably ok though. Put a meter across the battery with the engine running just to be sure. Should be around 14 volts or so. Same with the headlights and heater on. Check it at both idle and 2500 rpm.

 

[airhead04]

When doing the tests, would I need to allow the car to be at operating temp? Or does it not matter?

 

[whitemike]

JJ, do you think this is electrical for sure? Couldn't he be losing metered air, say, non-recirculated BOV? Let go of the gas, push the clutch, (BOV vents), car stumbles/stalls.. ?

Also, David, I have a spare alt you can pick up when I get back to Orlando if you need, or I can ship I suppose. It's ugly and old but it works like a charm.

As for diagnosing.. I've had a bad alt that didn't do anything above 3k or so RPM. Above that and the dash lit up like a Christmas tree and the motor ran like a moped. I'm also curious of the condition of your battery.

As always, LMK if you need anything brotha!

Mike

 

[jetjock]

Huh? I don't think it's electrical and even if it was the charging system isn't involved. Doesn't make sense it would be. Battery light is off, battery and connections are good enough to repeatably start the car (therefore good enough to run it if even the alt wasn't working), etc.

All I'm doing is teaching him how to do a basic check because I'd prefer he become less clueless than whomever suggested to him the problem is charging system related.

OP: The engine doesn't have to be warmed up....

 

[airhead04]

Ok, JetJock here is my results:

Before Starting the battery got a reading of 11.95v

Cold idle: 14.65v
Cold idle with lights: 14.61v
Cold idle with lights and heat: 14.67v

Op Temp: 14.55v
Op Temp and Lights:14.47v
Op Temp with lights and heat: 13.7v

2500rpms: 14.55v
2500rpms with Lights: 14.43v
2500rpms with lights and heat: 14.47v

Now when I had my lights on, and turned the heat on at operating temp, you could tell a drop in rpms. But then it came right back up to where it was. Another thing I noticed was the waterfall noise from behind the dash. But I dont think that would cause the rpm drop or cause the car to shut off.

Help please! =]

Thanks mike!

 

[jetjock]

As was suspected your charging system is fine. Forget about it and look elsewhere...

 

[airhead04]

Any ideas on what I should check?

Could loose grounds cause these types of symptoms?

 

[Satan]

Since U already plan to change starter... I'd suggest taking the replacement starter, alternator, and battery to an auto parts store that does "free" test/diagnosis (like Autozone). Yes, I know you tested the system, but sometimes there are intermittent failures of these components (or between them, like cables/connectors), leading up to some of your symptoms.

Now that you know these components are good, replace the starter and reinstall the other parts. Check the cabling, connections, and fuses (including AM1, AM2, fusible links) along the way. Just a good idea to knock everything out at one time, saving you time/hassle later.

If you still get the symptoms, chances are that your engine harness may be damaged/shorting. Check this also, if you had any recent work done. I had a short that left me stranded X-Mas eve on Alligator Alley one year... Took almost 8 hours to get a tow truck. Ain't fun to be on side of road, X-Mas eve, with your 8 year old son, freezing your asses off, and now a dead battery. We diagnosed/fixed the short later in Miami and I was able to drive back to Tampa.

Don't take any chances you don't have to.

Good luck!

 

[airhead04]

I do know my coil pack ground is VERY ragged. Can see bare wire on some places. As for the engine harness, its definitly seen better days, but seems to be ok. It just seems odd, because this problem is very random. Some days it never even hints of doing it. Others the rpms drop but never shut off. And just recently it has decided that its wanting to shut off. So my problem is definitly getting worse.

 

[jetjock]

The usual suspects. Vacuum, throttle linkage, ISC system, TPS, codes. A loose intake manifold ground would shut the ECU off. Loose grounds related to the fuel injectors or fuel pump circuit could also do it. Again though, I doubt the problem is electrical.

Hard to offer more because I don't know anything about how your car normally runs or what has been done to it. You just have to start from scratch. I knew the alternator thing was a waste but hey, you asked.

Btw it's "here are my results". "Are" should be used when speaking of things in plurality. Results result in more than one result

 

[airhead04]

Ok, thanks for the grammer help. Haha

Ill start from scratch then. And report my findings as they come.

Thanks for the help guys.

 

[jetjock]

Lol, it's "grammar"....and it's "alternator"

I point all that out because unlike some here you appear to make an effort when writing. In fact that's one reason I responded to your query in the first place.

It could be electrical I suppose. It could be a zillion other things too. Intermittent stuff can be a bear. One thing is for sure: when it finally doesn't work at all it'll be easy to find...