Hi, I'm a newbie, first time on. I took my 1984 2.5 for a spin one night and had no issues whatsoever, brought it home and parked it in the garage. The following night I went to hop in it and it would turnover but wouldn't start, so I poured some gas into the throttle body and it fired right and ran fine. There was No check engine light. I replaced the fusable links at the battery and the links near the starter checked out ok (is there another one somewhere?). Imput would be greatly appreciated. Thanks.
Do you hear the fuel pump power up when you turn the key to the on position? You should hear a whine for a few seconds as the pump pressurizes the line.
There is a fuel pump fuse under the drivers side dash. And as posted above, when you turn the key on, (with the key being off for at least 15 seconds) the pump will prime for 2 seconds, put your ear by the shifter and turn the key on, you should be able to hear the fuel pump, if so you are out of gas, if not check the fuse, then check the relay, behind the driver on the firewall, in the engine bay.
...it would turnover but wouldn't start, so I poured some gas into the throttle body and it fired right and ran fine. I replaced the fusable links at the battery and the links near the starter checked out ok
I'm missing something here. If the engine "ran fine" after you primed it with some gas down the TB, what issue were you looking for involving the fusible links?
If I understand this correctly, if there is no check engine light on when the ignition is on, and if there is no fuel at the TBI during cranking, then that is an indicator that there is no power to the ECM. So, when I supply the fuel by pouring a little in the TBI, the engine fires up and runs because power is supplied to the ECM from the alternator. Does that make sense? So yes the car runs fine once it is running...but there is no fuel during cranking. Thanks for the imput.
If I understand this correctly, if there is no check engine light on when the ignition is on, and if there is no fuel at the TBI during cranking, then that is an indicator that there is no power to the ECM. So, when I supply the fuel by pouring a little in the TBI, the engine fires up and runs because power is supplied to the ECM from the alternator. Does that make sense? So yes the car runs fine once it is running...but there is no fuel during cranking. Thanks for the imput.
Cold start injector is gone maybe, you said there are no codes when you turn the car on, is that using the proper procedure to check for codes? That light can just flash if there is a problem that you might not see every time or most times unless you are looking right at it. with the ignition the off position jump the A&B terminals and just turn the key on and wait for the code 12 flashes to flash 3 times, after that any fault codes will flash until they are all shown. it has been a while since I done a code check so I may be wrong about that but I am sure you can't see the fault codes unless the engine is in test mode.
Steve
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[This message has been edited by 84fiero123 (edited 12-13-2015).]
No cold start injector on the 84 duke. If the fuel pump relay is bad the car will start once you turn the engine over long enough to build up oil pressure. This is a back up so the car will still run with a bad fuel pump.
Try letting it turn over for 30 seconds or so to see if it will start. If you hear the fuel pump kick on as soon as you turn the key on, but not to the start position, the problem isn't with the relay.
I'm sorry if I wasn't clear, I didn't mean to indicate that there were no codes, though that is true. With the ignition on, the check engine light is not on...I had the understanding that if the check engine light didn't come on with the ignition in the "on" position, that was an indication of no power to ECM. Hence the search for a fusable link gone bad.
Yes on the check engine light HOWEVER, the ECM also runs the fuel pump relay. If the fuel pump is coming on for two seconds when you turn the key to on but don't crank, and then shutting off, the ECM is running. It could be that the check engine light is burned out, missing or just not making contact.
If however the fuel pump comes on only after cranking, and stays on for longer than two seconds, then the fuel pump is getting it's power via the oil pressure switch. GM designed the Fiero with the two ways of powering the fuel pump. So if it is only after cranking then proceed at looking why the ECM isn't running, with the most likely issue being no power to it.
Yes you are right Roadtrip that no check engine light usually means the ecm is not running, and as posted above the ECM is what kicks on the fuel pump relay for the 2 seconds, remember this, everything that needs power also needs ground, check your grounds. Also a bad Ignition Control Module will cause the injector not to fire, I have seen it on another 84. You can have any autoparts store test it for free, but you have to pull it out and bring it to them.
[This message has been edited by sardonyx247 (edited 12-13-2015).]
The ICM also produces the ignition spark that is clearly working. There is a remote remote chance that the ICM is working to produce spark but not for the ECM. That can be tested in the car however. The ECM has a function that it turns on the fuel pump relay also whenever it receives an ignition pulse. To test this turn the key on and let the fuel pump relay cycle. Then just bump the starter. If the ECM is working and is receiving ICM pulses the ECM will turn on the fuel pump for two seconds and then it will turn off again. This can be repeated again and again if needed. Note - don't crank the engine however as it will turn on the oil pressure switch. You will know if the oil pressure switch is activated since the fuel pump will stay on for much longer than two seconds.
[This message has been edited by phonedawgz (edited 12-13-2015).]
I'm missing something here. If the engine "ran fine" after you primed it with some gas down the TB, what issue were you looking for involving the fusible links?
And if the engine ran fine after pouring fuel into the throttle body, then the fuel pump fuse should be good, too, as well as all power sources to the fuel pump. I had this problem with the 88 Duke and I found that tapping on the injector while cranking would cause it to begin spraying. I cleaned the contacts on the injector with a slight improvement, but it eventually required replacing the injector.
The check engine light problem could simply be a burned out bulb.
Wow, thanks for all the response! So...yes fuel pump runs in the "on" position...and it also does a short run if the starter is bumped. If I deduce correctly, that's good news regarding power to the ECM. The car being new to me (all of 31,000 miles), that Check Engine light could easily been out without me knowing it. I will get my queen (it's her car) to turn it over while I tap the TB and wiggle a wire or two. Thank you so much. Dale
Trying to move ahead. If during cranking is the only time that I'm not getting fuel; should I swap out the ECM. Even though you have helped me prove that it is running...can it be the culprit? Dale
If tapping on the injector while cranking produces fuel it isn't the ecm. You can remove and clean the injector, just be careful to not drop any parts into the throttle body. Check to be sure vacuum lines are attached underneath the breather. If the engine has coughed or backfired it may have blown some loose especially the one for the MAP sensor.
First try cranking it for a few seconds if it still doesn't work, then it is like I said before the ignition control module. I have seen it happen on an 84 before.
Same result, crank and crank but nothing more. My apologies, through the discussion I thought the ICM had been rule out as a factor. Car sees my mechanic Wed. to verify the check engine light being burnt out, I'll steer him toward the ICM. Dale
Are you messing with the gas pedal when you're trying to start the engine?
And another question... Does it make any difference if the engine is hot or cold? In other words... if you prime the engine by pouring gas into the TB, and it starts and runs fine, how well does it start if you turn off the engine and then immediately go to re-start it?
[This message has been edited by Patrick (edited 12-14-2015).]
ICM may be faulty. I had an 84 with odd starting/fuel issues that turned out to be the ICM. They are only about $6.00 at rockauto, and it never hurts to have an extra. Good Luck
Not messin with the gas peddle, just lettin it crank.
Okay, good. Some people think they're still trying to start a '68 Ford Galaxie, and they mess about pumping the gas pedal to set the choke etc. Obviously this isn't required with a fuel-injected engine.
quote
Originally posted by Roadtrip:
Cold- never fires up Only tried it once hot and it fired up on its own.
So we know then the TB injector is getting gas (at some point) while the engine is being cranked. That's a positive sign.
The '84 duke does not have a cold-start injector like the 2.8 V6 does. I forget what it is that the duke relies on to richen the fuel mixture when the engine is cold, but it might just be the Coolant Temperature Sensor. I wonder if your CTS was faulty whether it might be telling your ECM that the engine is much hotter than it actually is... with the end result that the engine is trying to start with much too lean of a mixture when it's cold.
Do you have a scanner or WinALDL to see what the ECM is actually being told?
[This message has been edited by Patrick (edited 12-14-2015).]
Too funny, 'bout the Ford Galaxy! ...I have a toolbox that would allow me to isolate and expose the ECM, however, that would be as far as me technical trades go! I believe I will be home tomorrow at which time I will do some repeated "hot" restarts, and we'll see where that goes. Thanks, Dale
Just remembered...last trip to my mechanic, I left it running while I waited for him to clear a bay...the cooling fan didn't come on (and it had been functioning because I'd checked it, I was blaming the ECM) and it was running hot when I climbed in...Coolant Sensor???
...I have a toolbox that would allow me to isolate and expose the ECM, however, that would be as far as me technical trades go!
It's more the Coolant Temperature Sensor that I'm suspicious of. There are ways of testing it with a multimeter. If you can't find something about doing this in the archives, perhaps someone who's familiar with the process can chime in.
quote
Originally posted by Roadtrip:
Just remembered...last trip to my mechanic, I left it running while I waited for him to clear a bay...the cooling fan didn't come on (and it had been functioning because I'd checked it, I was blaming the ECM) and it was running hot when I climbed in...Coolant Sensor???
No. Check the diagram above. The fan won't be switched on until the coolant reaches 235°F (with the factory setup).
[This message has been edited by Patrick (edited 12-14-2015).]
Originally posted by Patrick: Okay, good. Some people think they're still trying to start a '68 Ford Galaxie, and they mess about pumping the gas pedal to set the choke etc. Obviously this isn't required with a fuel-injected engine.
Back when fuel injection was just starting to be popular for new cars in the early 80s like ours I had a neighbor who said he couldn't start his new celebrity, by some sort of weird coincident the very same car our plant was building when I was at GM. Being his first new car he had with fuel injection he had flooded the dam thing, you could smell the gas from 10' away.
To the OP I have an idea for you to try,
As you are cranking the engine if it doesn't start after a couple of rotations of the engine, slowly push down on the gas pedal to about half throttle while continuing to crank the engine. In real cold weather I will sometimes have to do that to get my 2.8 running for some unknown reason. But those are temps well under 0 F. Hey I have to move the dam car after every storm to plow the driveway.
if you haven't changed the fuel filter yet, do it now. Throttle body engines it is sometimes hard to see the spray from the injector, never mind the pattern of the spray. What I do to check them is use a timing light while cranking the engine, when it is flashing you will be able to see the pattern of the spray clearly and tell if it is clogged. It will also tell you if you are getting any fuel to the engine during cranking.
Thanks again for the imput. So appreciated! Yup, I just changed the fuel filter. Done the accelrator test. Haven't checked for spray while cranking. Just checked price of ICM up here in the Great White North ( not yet white!), 90 bucks!...will let my mechanic test it tomorrow. Just goin out to do some hot restarts. Dale
Ok, here's what I found. Cold start - nothin new, cranks over won't start. Pour in a little fuel and away it goes and stays running. Took it for a drive, got it good and warm and brought it home and shut it off. I did an immediate retry and it cranked and sputtered but didn't start, however, on the second retry fired right up. It did this same pattern a number of times. I'm thinking just because fuel was right ready and available, maybe? On cold starts try it as many times as you want with no results. So, I let sit for 20 mins. tried to make this message clear and then went out and it fired right as if nothing was ever wrong...but, on a retry sputtered and died, firing up once again on the second attempt. I'll search that link. Thanks.
