jmanghani

I have a 1999 V6 mustang automatic transmission. Yesterday, driving on the freeway at 70mph, I was around 2200 rpm, and then it felt like the car was going to stall but it went up to 3000+ rpm and then dropped back down after 2-3 seconds. The speedometer needle went to zero and then back up to 70. This has happened about 4-5 times since then, with the exception of the speedometer needle going to zero. I changed the air filter, since I live in SD and thought that all the ash in the air may be clogging up the air filter, but it happened a couple times today.

Any ideas what might be going on?

Jee

PRO50SC

What makes you think it's the tranny? Your description is kinda vague.

jmanghani

I think it might be the tranny because it went up to 3000rpm, as if it had downshifted into 3rd gear. But it's hard to tell whether it did or not.

jerimiahy16

I'm not 100 percent sure. However I have my doubts about it being the transmission at least lets hope not.

My truck at work had a similar problem however it ended up stalling out. Turned out to be some bad/old parts in the engine as we'll as a clogged battery.

I'd take it to the shop at the very least to get it diagnosed. It will more then likely stall out eventually.

If I had to guess I'm thinking the throttlebody. I know when I installed my aftermarket throttlebody I kept having to tinker with it as it kept starting up then stalling on idle.

l_shizzle_l

Are you throwing a CEL?

jmanghani

I'm sorry, but I don't know what a CEL is.

However, I do have more information. When I drove home yesterday evening, my engine died on the freeway after my speedometer went haywire. I pulled over, and successfully restarted the engine, with the same engine problems (felt like it was backfiring or something). I went to the gas station, filled up, and then my car wouldn't even start up. Turns out that the Theft protection prevented my starter from starting my engine. I disconnected the negative battery terminal, and basically reset the electrical system. The theft indicator went off, and the car started up. Also, I haven't had the engine shifting problem since.

I'm guessing that some electrical component got into a bad state, and this caused the shifting, dying engine, theft indicator problem? It has been very smoky and ashy here in San Diego, so maybe that had something to do with it....

Jee

rfcsoulja

CEL= Check Engine Light

mustangcrazy87

thats pretty crazy. I was going to say that you need to check your tranny fluid, but it looks like you fixed it. GOOD JOB!

Justin_R

It might beyour battery, mine was doing the same **** it was scary as ****, LOL! I had to replace it and now everything is fine.

jmanghani

Ok, so I didn't have any shifting problems. But half way to work, my engine died, with the little battery light lit up. Then I tried to restart, but the theft system had been tripped. So I removed the negative battery terminal for a few seconds and then put it back on. Then I was able to restart.

I just bought a new battery about a month ago....any ideas what could be going on?

Jee