Poor idle & Injector behavior
Thread Starter
8th Gear
Joined: Aug 2017
Posts: 8
Likes: 0
Poor idle & Injector behavior
So I recently acquired a 1984 Crossfire, and I've been noticing a few bugs I'm having trouble tracking down & finding answers for.
Upon first start up the car idles normal, but after about 15-20 seconds I notice it's a bit hesitant with it's idle. Then, as soon as I try to give it a little gas, it stalls out (~5% throttle) however anything above that is fine. I took off the air cleaner cover to look at the spray pattern and I noticed that when it's given little throttle, the injectors spray as much as they do if I gave it 80% throttle. I could really use some help with this if anyone has a solution.. thanks!
-B
Upon first start up the car idles normal, but after about 15-20 seconds I notice it's a bit hesitant with it's idle. Then, as soon as I try to give it a little gas, it stalls out (~5% throttle) however anything above that is fine. I took off the air cleaner cover to look at the spray pattern and I noticed that when it's given little throttle, the injectors spray as much as they do if I gave it 80% throttle. I could really use some help with this if anyone has a solution.. thanks!
-B
Thread Starter
8th Gear
Joined: Aug 2017
Posts: 8
Likes: 0
Thanks everyone. I will be looking into my TPS and possibly replacing it. Upon further inspection it looks like the wires have been tapped and it has a testing 'connector' added on. I also noticed yesterday that my brake light switch failed (my brake lights stayed on without me touching it), so I do believe that's contributing to my idle issue as well. I will update when I make some progress, but keep the suggestions coming!
thanks, -B
thanks, -B
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
There are a couple of sensors on a XFire that absolutely need to be dialed in or you car will not behave.
You will need to check your TPS, IAC, coolant sensor and MAP sensor. Cap your EGR if suspect.
Additionally your car is highly sensative to vacumm leaks. Check all the hoses that lead to the engine. Snip a 1/4 inch off the ends if you notice any cracks as it will give you a fresh seal.
Finally, low fuel pressure plagues these car. If you swap your filter and up grade to a higher pressure 85-89 (it will bolt right into your tank) pump you will feel a difference.
Good luck!
You will need to check your TPS, IAC, coolant sensor and MAP sensor. Cap your EGR if suspect.
Additionally your car is highly sensative to vacumm leaks. Check all the hoses that lead to the engine. Snip a 1/4 inch off the ends if you notice any cracks as it will give you a fresh seal.
Finally, low fuel pressure plagues these car. If you swap your filter and up grade to a higher pressure 85-89 (it will bolt right into your tank) pump you will feel a difference.
Good luck!
Last edited by billschroeder5842; Sep 1, 2017 at 03:55 PM.
Burning Brakes
Joined: Jul 2017
Posts: 750
Likes: 86
From: St Petersburg
So I recently acquired a 1984 Crossfire, and I've been noticing a few bugs I'm having trouble tracking down & finding answers for.
Upon first start up the car idles normal, but after about 15-20 seconds I notice it's a bit hesitant with it's idle. Then, as soon as I try to give it a little gas, it stalls out (~5% throttle) however anything above that is fine. I took off the air cleaner cover to look at the spray pattern and I noticed that when it's given little throttle, the injectors spray as much as they do if I gave it 80% throttle. I could really use some help with this if anyone has a solution.. thanks!
-B
Upon first start up the car idles normal, but after about 15-20 seconds I notice it's a bit hesitant with it's idle. Then, as soon as I try to give it a little gas, it stalls out (~5% throttle) however anything above that is fine. I took off the air cleaner cover to look at the spray pattern and I noticed that when it's given little throttle, the injectors spray as much as they do if I gave it 80% throttle. I could really use some help with this if anyone has a solution.. thanks!
-B
car runs better that ever
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Thread Starter
8th Gear
Joined: Aug 2017
Posts: 8
Likes: 0
Back with an update:
It seems like the problems been fixed. I ended up cleaning the IAC's, cleaned the TPS, replaced a yard or so of old and dry rotted vacuums line, and also found out my brake light switch was faulty. Learned about how it controls the TCC and so on so I replaced that and now my car idles close to how it should be, and does not stall when I try to drive forward (I think that was the brake light switches fault).
Again thank you all for your support. I have many more things to do to the vette and it's got its share of kinks I need to work out.
-B
It seems like the problems been fixed. I ended up cleaning the IAC's, cleaned the TPS, replaced a yard or so of old and dry rotted vacuums line, and also found out my brake light switch was faulty. Learned about how it controls the TCC and so on so I replaced that and now my car idles close to how it should be, and does not stall when I try to drive forward (I think that was the brake light switches fault).
Again thank you all for your support. I have many more things to do to the vette and it's got its share of kinks I need to work out.
-B