1985 Manual misfiring
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
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From: Nashville TN
2017 C4 of Year Finalist
wow man-thanks for all the advice! You've given me a lot to think about, and yeah I think it's ignition-related as well. A compression test is probably still a good idea though. I'm replacing that today and I'll post back results.
Team Owner
Joined: Jul 2004
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From: Hartford WI
I'd stop replacing parts and do testing before the hope and pray parts replacement
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
Found out a guy at my local O'Reilly's fixes up old TPI cars in his free time-including a lot of old Vettes. He definitely knows his way around that engine. First thing he pointed out was the TPS was way off center, and showed me how to adjust it. as soon as I did that, the engine started idling and running MUCH better. Still misfiring but it's a lot smoother in general and no more stalling. I'll have to use a multimeter to fine-tune it, but we ballparked it in the parking lot.
Compression tests will most likely be done this weekend, although we have family coming in from out of town, so I might have to delay into next week. Most of the parts that I've put on, I truly believe were worth replacing regardless of being the misfire source. But I agree-testing is important and I think I need to do that to figure out where to go next.
Compression tests will most likely be done this weekend, although we have family coming in from out of town, so I might have to delay into next week. Most of the parts that I've put on, I truly believe were worth replacing regardless of being the misfire source. But I agree-testing is important and I think I need to do that to figure out where to go next.
Team Owner
Joined: Jul 2004
Posts: 28,495
Likes: 3,298
From: Hartford WI
Found out a guy at my local O'Reilly's fixes up old TPI cars in his free time-including a lot of old Vettes. He definitely knows his way around that engine. First thing he pointed out was the TPS was way off center, and showed me how to adjust it. as soon as I did that, the engine started idling and running MUCH better. Still misfiring but it's a lot smoother in general and no more stalling. I'll have to use a multimeter to fine-tune it, but we ballparked it in the parking lot.
Compression tests will most likely be done this weekend, although we have family coming in from out of town, so I might have to delay into next week. Most of the parts that I've put on, I truly believe were worth replacing regardless of being the misfire source. But I agree-testing is important and I think I need to do that to figure out where to go next.
Compression tests will most likely be done this weekend, although we have family coming in from out of town, so I might have to delay into next week. Most of the parts that I've put on, I truly believe were worth replacing regardless of being the misfire source. But I agree-testing is important and I think I need to do that to figure out where to go next.
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Safety Car
Joined: Jan 2014
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From: Poughkeepsie New York
Just a thought, you mentioned the previous owner replaced the distributor and you get a knock code. What is your timing at? If it's off and the computer is pulling timing because it is sensing knock it will run rough.
Team Owner
Joined: Jul 2004
Posts: 28,495
Likes: 3,298
From: Hartford WI
Good point. Something to check is if the timing is off the wall since the harmonic balancer can separate and if it does, you have ridiculous timing readings but might be 6 degrees.
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
Team Owner
Joined: Jul 2004
Posts: 28,495
Likes: 3,298
From: Hartford WI
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
I'm thinking I will probably need to buy the Bosch III injectors sooner or later (probably sooner). I'm sure they're expensive, but does anyone here know how/where to get them cheaply? Also, since the last guy says he put on new injectors, is there a good way to make sure I don't already have the Bosch III injectors on there? I think they're yellow, from seeing pics. Those are the ones that you want to get, right? They handle ethanol in fuel better?
Team Owner
Joined: Jul 2004
Posts: 28,495
Likes: 3,298
From: Hartford WI
I'm thinking I will probably need to buy the Bosch III injectors sooner or later (probably sooner). I'm sure they're expensive, but does anyone here know how/where to get them cheaply? Also, since the last guy says he put on new injectors, is there a good way to make sure I don't already have the Bosch III injectors on there? I think they're yellow, from seeing pics. Those are the ones that you want to get, right? They handle ethanol in fuel better?
Give Jon Banner a call. https://fuelinjectorconnection.com/c...uilt-injectors
Oil Producer
Joined: Apr 2014
Posts: 9,380
Likes: 2,744
you need a piston stop tool to ensure that the the mark is actually in the right spot.
u can make one with an old spark plug and a nail or a bolt with jb weld. thats what i did. check out youtube.
Last edited by VikingTrad3r; Mar 18, 2017 at 01:57 PM.
Oil Producer
Joined: Apr 2014
Posts: 9,380
Likes: 2,744
IDK. There is a number on them. Without that, we are guessing. I can show you a set of yellow ones from FIC that are 32pph which is WAY too large. Scan for injector pictures and post it up. What is "yellow" to you might be "Orange" to me and so on.
Give Jon Banner a call. https://fuelinjectorconnection.com/c...uilt-injectors
Give Jon Banner a call. https://fuelinjectorconnection.com/c...uilt-injectors
ak is right. call jon.
85 has DIFFERENT injector lbs than the rest. i belive its 24lbs. but call him and ask!!
Team Owner
Joined: Jul 2004
Posts: 28,495
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From: Hartford WI
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
Some new info-I got the gauges working, and I'm getting a whopping 8 MILES to the gallon! whoop!
I feel like that's a little low considering I'm driving it like my grandma (who is not the little old lady from Pasadena).
I'm pretty sure it's related to the misfire. I'm actually not getting any codes on the ECM anymore (that's a good thing, right?) so I think as far as it is concerned, we're running pretty well. I still haven't done the compression test or checked timing, have to buy the stuff to do that first. Just thought the high fuel consumption might be a clue to what's happening.
I feel like that's a little low considering I'm driving it like my grandma (who is not the little old lady from Pasadena).
I'm pretty sure it's related to the misfire. I'm actually not getting any codes on the ECM anymore (that's a good thing, right?) so I think as far as it is concerned, we're running pretty well. I still haven't done the compression test or checked timing, have to buy the stuff to do that first. Just thought the high fuel consumption might be a clue to what's happening.