bump anybody?
Fuel/spark issue
I've got a 93 GT 5 speed. Nothing fancy on it. Full exhaust, gt-40 intake and cold air intake. That is about it. Anyway, it started freaking out on me today. It will act like it is running on 5 cylinders at random and will have minimal to no throttle response whatsoever. It does not do it at any specific time. Then after I jab the throttle a few times it goes back to normal. Then it does it a few minutes later. I have no idleing issues.
Here is what I know.
1. Oxygen sensors are brand new
2. Spark plugs & wires replaced 8 months ago.
3. Distributor cap and rotor were replaced 8 months ago
4. Fuel filter was replaced 6 months ago
5. Ignition coil was replaced 8 months ago.
6. Ignition control module was replaced today hoping that it was the problem
7. I think my fuel pump is good because I can hear it hum just before startup.
Anybody have any ideas? I'm a little lost. Is it possible my fuel filter is already clogged up? I've only put about 6000 miles on the car since getting it in February
Here is what I know.
1. Oxygen sensors are brand new
2. Spark plugs & wires replaced 8 months ago.
3. Distributor cap and rotor were replaced 8 months ago
4. Fuel filter was replaced 6 months ago
5. Ignition coil was replaced 8 months ago.
6. Ignition control module was replaced today hoping that it was the problem
7. I think my fuel pump is good because I can hear it hum just before startup.
Anybody have any ideas? I'm a little lost. Is it possible my fuel filter is already clogged up? I've only put about 6000 miles on the car since getting it in February
1 - 16 of 16 Posts
Mine was doing near the same thing (89 Lx 5.0) and after changing numerous parts to chase it down, I swapped the ECM out and that fixed it. Do you have another one to swap out and check it?
any CEL's??
I tend to believe fuel pump, or regulator. Although, I'd get the TFI tested and check your grounds.
I tend to believe fuel pump, or regulator. Although, I'd get the TFI tested and check your grounds.
No, I do not. I've never had a car do this before. I can drive and hold my foot steady on the throttle and then it will act like a couple of spark plug wires just got pulled off of it. Then it goes back to normal. Then a mile or two later, same issue. Does not matter what speed, gear or RPM range I am in.Mine was doing near the same thing (89 Lx 5.0) and after changing numerous parts to chase it down, I swapped the ECM out and that fixed it. Do you have another one to swap out and check it?
No check engine light. Grounds are all good and I replaced the TFI a few hours ago thinking that was the issue. I started thinking more and more that it is the fuel pump or fuel pressure regulator.any CEL's??
I tend to believe fuel pump, or regulator. Although, I'd get the TFI tested and check your grounds.
Honestly, I am leaning towards the fuel pressure regulator being that I can hold the throttle steady and it will start to freakout at random. What does everybody else think? I just don't want to throw more useless parts at it.
That is exactly what mine was doing... run rough for a few seconds and then clear up, then start again. If I clutched and reved it a couple times, it would clear up for a bit, then start over.No, I do not. I've never had a car do this before. I can drive and hold my foot steady on the throttle and then it will act like a couple of spark plug wires just got pulled off of it. Then it goes back to normal. Then a mile or two later, same issue. Does not matter what speed, gear or RPM range I am in.
What are the signs of a bad fuel pump?
What are the signs of a bad fuel pressure regulator?
maybe if you all could help define those issues I might be able to narrow it down
What are the signs of a bad fuel pressure regulator?
maybe if you all could help define those issues I might be able to narrow it down
Yup. That is what it is doing.That is exactly what mine was doing... run rough for a few seconds and then clear up, then start again. If I clutched and reved it a couple times, it would clear up for a bit, then start over.
Prior to the computer swap I changed the plugs, wires, cap, rotor, maf, tps, cleaned the IAC, fuel filter, and air filter.
Hmmmm.Prior to the computer swap I changed the plugs, wires, cap, rotor, maf, tps, cleaned the IAC, fuel filter, and air filter.
The fuel pump will typically make more or less noise on priming. If the regulator is bad, the fuel pressure goes way up and it will typically run like shit and smell REALLY rich.What are the signs of a bad fuel pump?
What are the signs of a bad fuel pressure regulator?
maybe if you all could help define those issues I might be able to narrow it down
There's a possibility that you have a bad injector or two. I'd start the car and spit or spray water on the header tubes one at a time while the car is full running temp. If the water bounces off, move to the next cylinder.. until you find one that the water is sticking to the header. It's the cheapest, tried and true problem solver.
Sounds interesting as well. Based upon what you are saying, I do not think the fuel pressure regulator or fuel pump or bad.The fuel pump will typically make more or less noise on priming. If the regulator is bad, the fuel pressure goes way up and it will typically run like shit and smell REALLY rich.
There's a possibility that you have a bad injector or two. I'd start the car and spit or spray water on the header tubes one at a time while the car is full running temp. If the water bounces off, move to the next cylinder.. until you find one that the water is sticking to the header. It's the cheapest, tried and true problem solver.
It could very well be the fuel pump or the regulator, but it sounds just like what mine did. I thought it was the fuel pump at first as well. I had all kinds of spare parts laying around to diagnose mine though. When it was all said and done, I changed the computer and it was running strong till I lifted the heads on it... :frown:
Here is how it was running just over 24 hours ago.
http://www.youtube.com/watch?v=mwB_KDjJcj0
It does not run like crap continuously and it does not smell like fuel. So I don't think the fuel pressure regulator is the issue.
http://www.youtube.com/watch?v=mwB_KDjJcj0
It does not run like crap continuously and it does not smell like fuel. So I don't think the fuel pressure regulator is the issue.
Running strong in the video...
http://www.dfwstangs.net/forums/showthread.php?t=389346&highlight=Running+problems
http://www.dfwstangs.net/forums/showthread.php?t=396261
Here are the threads that I posted, and updates as I was troubleshooting. I really think your having the same problems I was having... except the vacuum leak, blown head gasket part.
http://www.dfwstangs.net/forums/showthread.php?t=389346&highlight=Running+problems
http://www.dfwstangs.net/forums/showthread.php?t=396261
Here are the threads that I posted, and updates as I was troubleshooting. I really think your having the same problems I was having... except the vacuum leak, blown head gasket part.
1 - 16 of 16 Posts
- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
DFW Mustang Forums
A forum community dedicated to Dallas/Fort Worth area Mustang owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
Top Contributors this Month
View All
Diode Dynamics
5 Replies
smilingbutterfly39
3 Replies
reneepitcock95
2 Replies
