not charging until revved

[SHOguy]

I searched all over and didn't see anything on here, so here goes. My red 93 SHO will not charge after starting until it hits 1500 RPM. It has been doing this since I got it and hasn't gotten worse. until you rev it to 1500, it will run off the battery and will take the battery down til it dies, but if you tap the gas and bring it to exactly 1500, it will charge great, even going back to idle. When it charges, it is right about 14-14.5 volts, nice and happy. anybody seen this before? it is kind of wierd, especially since it hasn't gotten worse. always been exactly 1500 rpm.

 

[SHO#7]

I searched all over and didn't see anything on here, so here goes. My red 93 SHO will not charge after starting until it hits 1500 RPM. It has been doing this since I got it and hasn't gotten worse. until you rev it to 1500, it will run off the battery and will take the battery down til it dies, but if you tap the gas and bring it to exactly 1500, it will charge great, even going back to idle. When it charges, it is right about 14-14.5 volts, nice and happy. anybody seen this before? it is kind of wierd, especially since it hasn't gotten worse. always been exactly 1500 rpm.

Wrong pulley on the alternator? Or the alternator itself is bad.

Mike

 

[TYSHO]

I searched all over and didn't see anything on here, so here goes. My red 93 SHO will not charge after starting until it hits 1500 RPM. It has been doing this since I got it and hasn't gotten worse. until you rev it to 1500, it will run off the battery and will take the battery down til it dies, but if you tap the gas and bring it to exactly 1500, it will charge great, even going back to idle. When it charges, it is right about 14-14.5 volts, nice and happy. anybody seen this before? it is kind of wierd, especially since it hasn't gotten worse. always been exactly 1500 rpm.

I have the same problem on my 92 and the same rpm range that I need to rev it to. Doesn't happen everytime, though, more like 25% of the time and it hasn't got worse.

 

[jedhead]

I have UDP on my alt. It charges at idle 1100rpm (LPM equipped).

Bob

 

[TYSHO]

I have UDP on my alt. It charges at idle 1100rpm (LPM equipped).

Bob

The UDP's off the 89 they were originally on, and now the other 89, never required any type of chip. They seem to charge at idle [850ish rpms] no problem.

 

[jedhead]

I have the LPM to support the mods on my car. The 80mm requires the LPM to translate the output of the MAF correctly.

Bob

 

[TYSHO]

Oops, I mis-read, I thought you had [LPM required].

 

[SHO#7]

I guess you could check all connections too. Battery terminals. Ground straps.

Mike

 

[SHOguy]

it could possibly be the alternator, but it isn't getting worse. The wiring is fine and tight, and it has the right pulley

 

[94shoguy]

that happened to my 94, i know its a different alternator, But one of the wires came loose, i think the 93 alternator has only two wires, but check those connections good.

 

[smokin joe]

94shoguy Just thought i would tell you i hope you dont have a vtech sticker because it is vtec

 

[YAHTEC]

A failing diode will do that.. its not worth the rebuild so just replace you ALT

 

[Egg]

I had that happen to my car. It took a long time for the alt to finally go. When it did it i smelt somthing electric burning on the way to work one morning, i stoped to get somthing to drink and when i started my car everything died. i poped the hood and there was my alt with all the windings melted and insulation uzzing out of the vents. $180 later and everything runs much better. While i was at it i changed the belt.

 

[Drummaster788]

A failing diode will do that.. its not worth the rebuild so just replace you ALT

my '94 does the same thing...as a matter of fact it died on me this moring..left me stranded on my way to school....i was thinking of getting the alternator rebuilt, buying a new one or buying a new battery..which should i do? im also thinking of getting rid of the whole car all together. (dreading the thought though)

 

[TYSHO]

my '94 does the same thing...as a matter of fact it died on me this moring..left me stranded on my way to school....i was thinking of getting the alternator rebuilt, buying a new one or buying a new battery..which should i do? im also thinking of getting rid of the whole car all together. (dreading the thought though)

Just because your alternator? Where in Texas are you?

 

[ManySHOs]

I just paid $95 to have my 93's 90a alternator rebuilt. (voltage regulator needed to be replaced). AZ wanted $200 for this unit with a 4 day wait to get it. Rockauto had the same part (same rebuilder) for $126 with a lower core charge. AZ probably would've pricematched rockauto but it only took the guy a few hours to beadblast, clean and rebuild my alternator. In my case it was worth having it done.

I took it to him in pieces. If I had the time, I would've just ordered the regulator and replaced it myself. The problem is that I don't have consistent access to a press which is needed to assemble and disassemble the alternator.

Moral of the story: it might be worth it to have it rebuilt locally. Try taking the car to Autozone or a similar place that will test it for free. Make your decision after you've figured out what it is. (I knew mine was failing because it was outputting 12.3v with no load on it)

Ian

 

[Drummaster788]

yea this morning it died and nothing would come on..the locks wouldnt open no hazard lights and it was in rowdy traffic so i ****** off alot of people...i took it to my uncle and he said the battery is bad and that it was bubbling or sumthin like that. the alternator is the only thing wrong with the car....but yea im in san antonio. i really dont wanna sell it and if i did id buy another SHO but i dont know wats going on with the thing so i dont know...yea..

 

[TYSHO]

yea this morning it died and nothing would come on..the locks wouldnt open no hazard lights and it was in rowdy traffic so i ****** off alot of people...i took it to my uncle and he said the battery is bad and that it was bubbling or sumthin like that. the alternator is the only thing wrong with the car....but yea im in san antonio. i really dont wanna sell it and if i did id buy another SHO but i dont know wats going on with the thing so i dont know...yea..

Well, it's just plain dumb to sell a car and buy the same kind for one problem. You'll probably have bad luck and end up in the same situation within a week. A new battery and alternator replaced beats the heck out of selling and buying a new SHO with the title transfer fees and what not.

If you need someone to work on your SHO, give DHMag a PM. He lives in Kerville and is usually willing to travel to work. I wouldn't hesitate to have him work on a SHO, that's if you need someone to do the work.

 

[Endri_SHO]

Well, I Had The Same Problem Once In My 92 Sho And That Turned To Be The Voltage Regulator, When I Took The Alternator To Have It Rebuilt..

Good Luck

Endri

 

[Hiboost]

My battery light comes on sometimes when the car is at low rpms..