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Iron duke no power under load by Fadingaway
Started on: 12-16-2013 07:35 PM
Replies: 23 (1174 views)
Last post by: Patrick on 12-19-2013 04:35 PM
Fadingaway
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Report this Post12-16-2013 07:35 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
I just got my third Fiero and its a 1984 iron duke automatic. Just like my first one. There are a few problems with it I am not pleased with
but my main concern is the lack of power, the car barely reaches 50 mph on top of that the tachometer is wayyy off as soon as you start the car it reads 3000 rpm but you can hear the rpm is nowhere near that. Sometimes coming to a stop the car will die. It has new plugs wires, the intake hat is gone and its missing alot of vacuum lines from what I can see. If anybody has an idea what's going on let me know, the map sensor and EGR are hooked up.
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deceler8
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Report this Post12-16-2013 07:45 PM Click Here to See the Profile for deceler8Click Here to Email deceler8Send a Private Message to deceler8Edit/Delete MessageReply w/QuoteDirect Link to This Post
You'll probably find the fuel pump is kaput.

It's a little difficult to check fuel pressure on a Duke, but you can jumper the fuel pump and try a volume check.

Get all the vacuum lines hooked up where they're supposed to go prior to trying to drop the tank.

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Gall757
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Report this Post12-16-2013 08:28 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Fix the vacuum lines. The RPMs may drop a bit after that.

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Patrick
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Report this Post12-16-2013 09:43 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Fadingaway:

I just got my third Fiero and its a 1984 iron duke automatic... the car barely reaches 50 mph


Isn't that normal for a duke automatic?

Hey, I'm allowed to tease you because I have an '84 as well... although I swapped a 5-spd into it. Varoooom!
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Fadingaway
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Report this Post12-17-2013 11:38 AM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well went out and played with the vaccum lines as soon as I started the car it sounded like there was a huuuuge vacuum leak only to find out it was actually the TB spraying so hard it sounds like a vaccum leak
I went threw and plugged all of the bad leaks and nothing happened I unplugged the vacuum line to the egr and its still doing the same thing. Anyone know what's up with this mess? If I had the money I would already be swapping out this god forsaken thing
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Gall757
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Report this Post12-17-2013 03:30 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
If you can describe the condition of your car, perhaps we can figure out what it needs. Are the vacuum lines all working now?
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Fadingaway
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Report this Post12-17-2013 03:57 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
The body and most of the interior are nearly immaculate the engine bay needs alot of love the wiring harness is all over the place and alot of the stuff is hashed together, I'm honestly surprised it runs. I plugged all of the iffy vacuum lines and everything seems normal based off of the diagram. I haven't tried driving the car due to the piles of snow and fear of the car getting stuck. Under heavy throttle trying to move the car you can hear it bog out and start to miss
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Gall757
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Report this Post12-17-2013 04:17 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
If there are no codes flashed, the next thing would be fuel pressure. Is the fuel filter good? How did the wiring get so messed up?
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2.5
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Report this Post12-17-2013 05:22 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Plugged up catalytic converter could be lack of power?
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Fadingaway
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Report this Post12-17-2013 07:51 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
I doubt its the cat as its not the original and the fuel filter is brand new. The only thing I haven't checked is the cap and rotor
and I still can't figure out this tachometer problem 3000 rpm just is not right and when you rev the motor it tries to wrap all the way around. I need to find a fix for the radiator fan before anything though. Anyone know how to wire up a quick on/off switch
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Report this Post12-18-2013 09:44 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Is it getting hot? What made you determine it needs rad fan work?

You may want to make sure the timing is correct, as a cause of lack of power too.

[This message has been edited by 2.5 (edited 12-18-2013).]

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2.5
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Report this Post12-18-2013 09:50 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Fadingaway:

Well went out and played with the vaccum lines as soon as I started the car it sounded like there was a huuuuge vacuum leak only to find out it was actually the TB spraying so hard it sounds like a vaccum leak


I doubt you will be able to hear a vacuum leak with the air cleaner lid (intake hat) missing.
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Fadingaway
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Report this Post12-18-2013 10:01 AM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
I did the normal tricks to try and turn the fan on when the car started to get hot. I opened the bonnet and lone behold the harness that plugs into the fan is missing and the fan is a Jerry rigged the plug harness is chopped and is only Being held on the. Radiator by one bolt and a zip tie
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Fadingaway
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Report this Post12-18-2013 01:02 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well I got some new vaccum lines and changed alot of the stuff that was just straight up weird. Found out the IAC is bad and I think the cat is plugged I pulled out the O2 sensor and the car ran alot better it actually had some power but for some reason it started to backfire a little bit. The cap rotor and wires are all new. So I'm thinking this is a fuel/ vaccum thing I also changed the map sensor. I'm going to cut off the catalytic converter and see what happens
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Report this Post12-18-2013 01:13 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Sounds like you are getting there. After that, if its still funky maybe check timing.
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Fadingaway
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Report this Post12-18-2013 04:13 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well I checked the pcv valve to see if its any good and... Its gone wtf? Could be causing some of my issues. Since the IAC is stuck what issues does it normally cause?
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Fadingaway
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Report this Post12-18-2013 05:13 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nevermind found the pcv valve. Now I have to throttle the car to keep it going. But I am on empty so I think its just out of gas. I will put some gas in it later and find out
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Report this Post12-18-2013 05:15 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Fadingaway:

Nevermind found the pcv valve. Now I have to throttle the car to keep it going. But I am on empty so I think its just out of gas. I will put some gas in it later and find out




#1 got fuel?
#2 got spark?

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Fadingaway
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Report this Post12-18-2013 05:41 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have fuel and spark, I just have to press the throttle to start it and it doesn't stay running long, I'm starting to lean toward a fuel issue now but it seems normal at idle it sprays just enough fuel to stay alive and when you move the throttle it sprays more fuel. The car sound alot better now that the vacuum lines are in order. I need to get this thing healthy enough to get it over to my friends garage grrrr. I don't have the resources to drop the tank right now to see if the fuel pump is taking a crap
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mike-ohio
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Report this Post12-18-2013 06:01 PM Click Here to See the Profile for mike-ohioClick Here to visit mike-ohio's HomePageClick Here to Email mike-ohioSend a Private Message to mike-ohioEdit/Delete MessageReply w/QuoteDirect Link to This Post
check-
timing
clogged cat
egr not closing - common issue
fuel pressure - not always pump - line between pump and hard line splits
compression - sometimes ring just worn out
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James Bond 007
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Report this Post12-19-2013 11:55 AM Click Here to See the Profile for James Bond 007Send a Private Message to James Bond 007Edit/Delete MessageReply w/QuoteDirect Link to This Post
Might be the fuel pressure regulator,but if its been sitting for more than a year,its internal tank rust and the fuel pump (fixable). Read my post here:
http://www.fiero.nl/forum/Forum1/HTML/088012.html

[This message has been edited by James Bond 007 (edited 12-19-2013).]

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Fadingaway
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Report this Post12-19-2013 12:22 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
EGR is good, next I will check the cat since I pulls the o2 the car actually had some power. Then its timing the gas tank will be last. I know the idle problem is the IAC is stuck
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Fadingaway
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Report this Post12-19-2013 04:16 PM Click Here to See the Profile for FadingawayClick Here to Email FadingawaySend a Private Message to FadingawayEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well now the problem in having is the car won't stay running unless you have your foot on the throttle, in fact it won't even start. I checked the plug wires and they were advanced two posts on the distributor so moved them back two posts and the car wouldn't start. I advanced each wire one post and it runs but still won't start without my foot on the pedal. Would the broken AIC valve cause this?
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Patrick
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Report this Post12-19-2013 04:35 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

As has been mentioned several times, you need to get a timing light on there.

No point messing about with other things if something as basic as ignition timing is off.
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