Pennock's Fiero Forum
  Technical Discussion & Questions - Archive
  WTF? car freaks out on acceleration.

T H I S   I S   A N   A R C H I V E D   T O P I C
  

Email This Page to Someone! | Printable Version


WTF? car freaks out on acceleration. by 07Hoffmannd
Started on: 05-11-2008 12:12 PM
Replies: 11
Last post by: Fierobsessed on 05-13-2008 03:11 PM
07Hoffmannd
Member
Posts: 404
From: St. Louis, Mo. U.S.A
Registered: Apr 2008


Feedback score: N/A
Leave feedback

Rate this member

Report this Post05-11-2008 12:12 PM Click Here to See the Profile for 07HoffmanndClick Here to Email 07HoffmanndSend a Private Message to 07HoffmanndDirect Link to This Post
anytime i accelerate my car freaks out. the tach goes crazy and twiches and my car almost dies. sometimes it does. the really wierd thing is that, that ding noise that tells you your lights are still on if you open your door goes off when i accelerate. it's anoyying and freaks me out. what's wrong with my car?

- 84' duke atutomatic -
IP: Logged
PFF
System Bot
ryan.hess
Member
Posts: 20784
From: Orlando, FL
Registered: Dec 2002


Feedback score: (1)
Leave feedback





Total ratings: 319
Rate this member

Report this Post05-11-2008 12:35 PM Click Here to See the Profile for ryan.hessClick Here to Email ryan.hessSend a Private Message to ryan.hessDirect Link to This Post
Check your battery cables for corrosion and tightness
IP: Logged
FieroJimmy
Member
Posts: 703
From: Mechanicsburg, PA
Registered: May 2002


Feedback score: (3)
Leave feedback

Rate this member

Report this Post05-11-2008 01:06 PM Click Here to See the Profile for FieroJimmySend a Private Message to FieroJimmyDirect Link to This Post
When the car dies, does it lose all electrical power for a moment, or does the engine just stall?

If the chime sounds consistently when accelerating and/or the car loses all power, I would look toward a battery/cable/ground problem. When you check the cables, make sure to check both ends.

If the chime is pretty random, it may not be connected to the stalling issue. By itself it is a fairly common failure.

When was the last time you did a tune up on the car? If the ignition system is in the process of failing you can get similar symptoms (though, not the chime).

When you are just cruising/idling, does the tach jump around? Does it only jump on hard acceleration, or does even light throttle produce symptoms?
IP: Logged
maryjane
Member
Posts: 65984
From: Cleveland Texas
Registered: Apr 2001


Feedback score: (4)
Leave feedback





Total ratings: 442
Rate this member

Report this Post05-11-2008 02:51 PM Click Here to See the Profile for maryjaneSend a Private Message to maryjaneDirect Link to This Post
Sounds like a charging problem--perhaps something simple as a slipping alternator belt--or naybe a bad voltage regulator in the alternator. Try to notice what your volt gage indicates when you accellerate.

As stated, a bad ground could cause it as well. Perhaps grounding back thru something because of a bad connection.
IP: Logged
FieroJimm
Member
Posts: 331
From: VA Beach VA
Registered: Nov 2007


Feedback score: N/A
Leave feedback

Rate this member

Report this Post05-11-2008 04:23 PM Click Here to See the Profile for FieroJimmSend a Private Message to FieroJimmDirect Link to This Post
Bad TCC? sounds like the symptoms as for the dingy it is going south or it is lose

[This message has been edited by FieroJimm (edited 05-11-2008).]

IP: Logged
maryjane
Member
Posts: 65984
From: Cleveland Texas
Registered: Apr 2001


Feedback score: (4)
Leave feedback





Total ratings: 442
Rate this member

Report this Post05-11-2008 05:29 PM Click Here to See the Profile for maryjaneSend a Private Message to maryjaneDirect Link to This Post
Bad TCC will usually manifest itself during stopping. The engine will die because the TCC doesn't disengage.. Perhaps the same holds true for accelration.
IP: Logged
katatak
Member
Posts: 7136
From: Omaha, NE USA
Registered: Apr 2008


Feedback score:    (8)
Leave feedback





Total ratings: 82
Rate this member

Report this Post05-11-2008 05:47 PM Click Here to See the Profile for katatakSend a Private Message to katatakDirect Link to This Post
Bad Ground?
IP: Logged
Matthew_Fiero
Member
Posts: 2699
From: Winnipeg,Manitoba,Canada
Registered: Aug 2001


Feedback score: (1)
Leave feedback

Rate this member

Report this Post05-11-2008 09:45 PM Click Here to See the Profile for Matthew_FieroClick Here to Email Matthew_FieroSend a Private Message to Matthew_FieroDirect Link to This Post
check battery for swelling
check battery connections
CHECK THE LITTLE GROUND FROM THE NEG BATTERY CABLE TO CHASSIS
check the distribution block directly under the c500 plug in the engine bay. See if any of those ring terminals are corroded.
Check braided neg ground cable.

trust me.. I had a bad battery and caused this as well as severe backfiring!
IP: Logged
07Hoffmannd
Member
Posts: 404
From: St. Louis, Mo. U.S.A
Registered: Apr 2008


Feedback score: N/A
Leave feedback

Rate this member

Report this Post05-13-2008 12:07 AM Click Here to See the Profile for 07HoffmanndClick Here to Email 07HoffmanndSend a Private Message to 07HoffmanndDirect Link to This Post
well. my car died. it would not start at all. no trying to start, no click from the stater/solenoid, no nothin. the dials don't even come on when i turn the car on (but not turned over). however, the lights all still work. and it makes the warning chime that my lights are on. the radio doesn't work though.

to answer some questions. the tach only goes crazy when i accelerated. not hard acceleration per se, but any acceleration that was above 2000 rpm. the car would seem like it was dying. it wouldn't jog or sound different. it just died. everything turned off and i came to a stop. it did this before and it magically started the next day (after i got it towed of course). i have no idea what happened to it, and niether does the local mechanic. also, the chime was random and only happened during acceleration.

note: battery is good. charger/ altornator new and not slipping. new connection from battery to altornator. and new clean connections to battery.
IP: Logged
Myke
Member
Posts: 415
From: Mid West City, OK, USA
Registered: Sep 2003


Feedback score: N/A
Leave feedback

Rate this member

Report this Post05-13-2008 10:23 AM Click Here to See the Profile for MykeSend a Private Message to MykeDirect Link to This Post
 
quote
Originally posted by 07Hoffmannd:

well. my car died. it would not start at all. no trying to start, no click from the stater/solenoid, no nothin. the dials don't even come on when i turn the car on (but not turned over). however, the lights all still work. and it makes the warning chime that my lights are on. the radio doesn't work though.

Am I wrong, or does this sound like a fusible link? (actually, sounds like about 6 problems at once) Also sounds like a bad solenoid, blown fuses, relays, neutral safety switch...... the "nothing but lights" thing is weird...let's try this, you need to weed out problems one by one... if the starter is not working, makes sure your in park. (you have an auto, correct?) If still no start, set the e-brake, press the brake, turn the key to "start" and hold in start position. slowly pull the shift lever down to "1". Note if the car tries to start in any gear.

Another thing to try is disconnecting the neutral safety switch (small rectangular type thing on the top of the transmission. about 2" X 2.5") and jumping the wires in the harness... someone here is going to have to help you with this because I have not owned an auto since.....2001(?). Try to start the car again (in park). If this lets you start the car, it will allow you to start in any gear. Be careful until you replace the safety switch.

Next we can look at the starter. Take a multimeter and and test the terminal with the thicker wire attached to it (should be the highest post) you should have 12v.

Now you need an assistant. The other post with the thinner wire (more towards the passenger compartment. terminal "S") should give you 0v, but when the key is turned to start, you will get about 10V. (this is why you need an assistant.) If you are getting the proper voltage but the starter is not working, your solenoid is shot. (the solenoid is the smaller part attacher to the starter. that has the wires attached to it)

I know you have other problems going on, but you need to get the car to run. I always start were I find my first problem when I get to the car (IE. you have to start the car before it runs, it has to run before you drive...)

 
quote

to answer some questions. the tach only goes crazy when i accelerated. not hard acceleration per se, but any acceleration that was above 2000 rpm. the car would seem like it was dying. it wouldn't jog or sound different. it just died. everything turned off and i came to a stop. it did this before and it magically started the next day (after i got it towed of course). i have no idea what happened to it, and niether does the local mechanic. also, the chime was random and only happened during acceleration.


note: battery is good. charger/ altornator new and not slipping. new connection from battery to altornator. and new clean connections to battery.


Sounds like something is grounding out....or more likely, not grounding. These cars are almost 25 years old, and over time the ground connections begin to corrode. You can replace the ground, or if they are good, scuff up the grounding spot and/or the wire ends. Or, if you wanted, you could just run new grounds to new spots.

You know, I wonder how the pick up looks on you car...

Just curious, is your wiring harness melted, or melting together? The main harness over the manifold (you said 84' correct?) can "melt" and expose the wires.... this can make them arch signals, ground out, or other weird things... When the car gave up, you were driving it for a while, and then "all of the sudden" the problems came up? or was it a constant thing? did you get one symptom at a time. (does anyone else see what I am getting at?) My old 84 auto melted the harness and the wires began to touch, arch, and ground... I thought the car was possessed... I called my mechanic to help be retrieve the car. When I explained what was happening, he thought I was joking. He saw the same things, and told me to call a priest. Got a new harness, and presto! car was perfect...

Just bouncing some ideas to you, and some easy checks and inexpensive items.

Keep us updated
Myke
IP: Logged
NashvilleFiero
Member
Posts: 555
From: Nashville, TN
Registered: Apr 2008


Feedback score: (1)
Leave feedback

Rate this member

Report this Post05-13-2008 10:31 AM Click Here to See the Profile for NashvilleFieroSend a Private Message to NashvilleFieroDirect Link to This Post
 
quote
Originally posted by Matthew_Fiero:

check battery for swelling
check battery connections
CHECK THE LITTLE GROUND FROM THE NEG BATTERY CABLE TO CHASSIS
check the distribution block directly under the c500 plug in the engine bay. See if any of those ring terminals are corroded.
Check braided neg ground cable.

trust me.. I had a bad battery and caused this as well as severe backfiring!


I have a similar issue. Not sure what the c500 plug is.
Brit

------------------
If you ever have a questions about the sincerity of the circle of Fiero owners on this site, take a look at:
"In Memoriam: Fiero Members"

Pretty impressive.....

IP: Logged
PFF
System Bot
Fierobsessed
Member
Posts: 4782
From: Las Vegas, NV
Registered: Dec 2001


Feedback score: N/A
Leave feedback





Total ratings: 147
Rate this member

Report this Post05-13-2008 03:11 PM Click Here to See the Profile for FierobsessedClick Here to Email FierobsessedSend a Private Message to FierobsessedDirect Link to This Post
Your problem is perfectly consistant with the main fuseable power links. This problem is somewhat unique to 84's and is VERY VERY common due to their location.

From the starter solenoid's stud is three wires, one fat one that goes strait to the battery, then two ring terminals with fuseable links, these supply power to the entire car. One does mostly lights, the other, everything else. Engine movement, (mostly acceleration) will wiggle these wires and cause power cutouts, then back on. You'll recognize these as things that happen when you first turn the key, you get a ding, and the guages jump back to life.

This problem can occur on later models, but the C500 connector (the one your 84 has on the firewall) and the fuseable links got moved to between the battery and the strut tower on 85's and later. Since there is no movement there, the fuseables rarely fail. This is what matthew_fiero is talking about. But you have an 84, so its not located there.

Damn 84's.

Quick suggestion, turn your ignition on, and grab the harness infront of the engine give it a wiggle, your car will magically come alive if I am right about the links.

84s.
IP: Logged



All times are ET (US)

T H I S   I S   A N   A R C H I V E D   T O P I C
  

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock