RPMs playing games with me

[Misterio]

I have no idea where to start with this problem. Recently when I am driving my car around the 2.5 ~ 3 rpm range my car kind of stutters and the RPM needle goes up and down quiet a bit (not normal its fast!). Usually when im in 1st gear going into 2nd is the worst where it kinda feels like its about to turn off. I thought maybe my injectors... so i put some injector cleaner but it didn't help.

Well recently i had a mechanic work on my alternator because my headlights where dimming but thats not a problem anymore, but i dont know if he messed anything up. Anybody have any ideas on what the problem might be?

thanks!

 

[Misterio]

anybody?

 

[shift_racer]

Did the mechanic replace the alternator or what kinda "work" did he do? This happend to me once too. I just replaced the whole alternator and it fixed the problem. Also check the terminal connections and clean them to make sure the battery is getting all the charge.

 

[FORMONTOYA]

Is it just the tach needle that's erratic or is the engine rpms erratic. Any other electrical type problems. The reason I ask is that I had a crank pulley go out that caused the tach to be erratic, lights dimming, comming on/going off at irregular intervals...basically causing havoc. Fixed the pulley and solved the problem.

 

[Misterio]

He said there was some bolt that was not tight and he tightened it on the alternator, then he put new terminals on the battery so i know they are clean and tight. Its not just the tach needle ### when the needle goes down my car slows down and jerks backwards somewhat. Where is this crank pulley????

 

[Misterio]

anybody?

 

[EclipseTrbo420A]

anybody?

Why dont you look over the connections on the alternator and the battery's Pos,neg and ground. Im not sure where the alternator is on the 420A ( its been a long time haha ) but I know the RPM gets its signal from a plug on the tranny...check that good luck It sould be visable somewhere on top of the tranny. I dont know if it will fix it or not but why not look! goodlcuk

 

[Misterio]

no its not just the rpm needle being erratic.. the actual engine is being erratic and now its gotten 1000 times worse.. it smells real bad like gas inside the car and it even makes my eyes watery.. from the fumes im not sure if its exhaust being dumped in my car or other stuff but i have not clue whats wrong with it.. i took it to autozone to get tested for the engine light and they said it was either 1. ignition system or 2. engine misfire... any ideas this is getting really bad please help a bro out

 

[Hyland33]

Some possible problems assuming this happens when your on the throttle

1. Fuel pump could be faulty
2. Loose Fuel Injector Wire Harness Connectors
3. vacuum leak

 

[freshlane]

have a datalogger?

 

[sniver]

How about the ECU? They can cause bucking ,and all sorts of twilight zone moments. I'm just not sure if it is as applicable on a 95 ,like it is on earlier 1g's. Hope you get this fixed.

 

[WOTDSM]

Could be ECU because my stock boost guage was erratic but the car ran fine up until a few days ago... So maybe the guage is a sign of the ECU going?

 

[sniver]

their is info on vfaq about the ecu. I suggest you read it and check your it, if you find bad caps and replace them early then you might not have to replace the whole thing. If you've ever any fish smell ,then it is a bad sign. Is the rpm oscillation accompanied by a temporary loss of power?

 

[Misterio]

I don't have a datalogger and I wouldn't know how to use one as for what hyland33 said about it could be the fuel pump: my cousin also suggested it could be the fuel pump as well, when i changed the fuel filter i took the pump out and put it back in because i didn't know where exactly the filter was... maybe i put it back on wrong. as for the loose fuel injector harness or vacuum leaks i wouldn't even know how to start trying to fix that. and for what sniver said: yes the rapid rpm oscillation is accompanied by a loss of power, a horrible jerking back and forth of the car and no acceleration. then the inside of the car starts smelling really bad like gasoline or exhaust fumes

 

[sniver]

Do you by chance also hear clicking inside the center console when this happens?

It's also possible that just the ignition solenoid or related part is at fault ,BUT so far it sounds like the ecu craps out, making the spark cease and fire rapidly, and just blowing the gas through w/o burning it 1/2 the time ,and when it does fires , it's to rich or flooded ,hence why you smell gas strongly ,and have no power and it jerks when it happens.

-this has happened to me, and the ecu was my problem-

* I managed to miss the 95 n/a aspect of this initially , but as far as I know, what I said is still pertinent. My apologies*

 

[luv2rallye]

I would say Sniver's comments are the most likely. Two other possibilities are an intermittant ASD relay or bad filter capacitor.