1994 Bogging Issue
Thread Starter
3rd Gear
Joined: Oct 2023
Posts: 3
Likes: 0
From: Nashville, TN
1994 Bogging Issue
Hello Everyone,
I have had a 1994 C4 (6 speed, 78,000 miles) for around 2 months now. Just in the last few weeks I began to notice the following issues:
(1) When accelerating under load regardless of gear, the engine will hiccup and bog pretty badly. If the car is in neutral, it has no issues going from idle to 4-5000 RPM. The bogging issue happens when under load of any sort, especially when going up a hill.
(2) Sometimes when I start the car, it will idle and rise between 500-1000 RPM.
I had the fuel filter replaced and oil replaced last week, but it did not seem to fix the issue. I am thinking the next thing to fix is spark plugs and spark plug wires.
Does anyone have any idea what may be causing this problem or have any solutions?
Thank you,
Dean
I have had a 1994 C4 (6 speed, 78,000 miles) for around 2 months now. Just in the last few weeks I began to notice the following issues:
(1) When accelerating under load regardless of gear, the engine will hiccup and bog pretty badly. If the car is in neutral, it has no issues going from idle to 4-5000 RPM. The bogging issue happens when under load of any sort, especially when going up a hill.
(2) Sometimes when I start the car, it will idle and rise between 500-1000 RPM.
I had the fuel filter replaced and oil replaced last week, but it did not seem to fix the issue. I am thinking the next thing to fix is spark plugs and spark plug wires.
Does anyone have any idea what may be causing this problem or have any solutions?
Thank you,
Dean
Team Owner
Joined: Jul 2006
Posts: 22,812
Likes: 485
From: Douglas County WI
I suggest you find a shop that has an engine analyzer (Sun machine we called them in my youth. Sun was the manufacturer.). They can provide all kinds of info on the health of your engine. I had s a similar problem with my 93. Started throwing parts at it to no avail until it was hooked up to engine analyzer. Opti spark was bad, as I suspected and of course that is the priciest thing that could go wrong.
Pro
Joined: Jan 2022
Posts: 689
Likes: 245
From: Spokane Wa.
I would be checking the fuel pump pressure. You can get a cheap pressure tester from Harbor Freight for less than $30 if they haven't gone up in price. I had to teflon tape one of the fittings on mine but after that it works fine. The symptoms you are describing are very likely related to low fuel pressure. It could be either a failing pump or a plugged up sock on the pickup tube in the tank. The other thing to check is your fuel pressure regulator. Pull the hose off it and if there is gas in it you likely have a failing regulator.
Most everyone on here will recommend that you get the factory service manuals for your year specific model if you intend to do your own work on the car. If you are at all mechanically inclined I would go after it that way as taking these cars to the shop every time you have some hiccup can get expensive very fast. Also, the search tool here on the forum is your friend as most everything you might encounter on a C4 most likely has been experienced before and dealt with by all the helpful folks on here.
Most everyone on here will recommend that you get the factory service manuals for your year specific model if you intend to do your own work on the car. If you are at all mechanically inclined I would go after it that way as taking these cars to the shop every time you have some hiccup can get expensive very fast. Also, the search tool here on the forum is your friend as most everything you might encounter on a C4 most likely has been experienced before and dealt with by all the helpful folks on here.
Thread Starter
3rd Gear
Joined: Oct 2023
Posts: 3
Likes: 0
From: Nashville, TN
Hello,
Thank you for the reply. I bought a fuel pressure tester and drove around and was having 35-40 PSI. So I am thinking the fuel pump is fine but if you have any ideas Ill gladly and desperately take them.
Thank you for the reply. I bought a fuel pressure tester and drove around and was having 35-40 PSI. So I am thinking the fuel pump is fine but if you have any ideas Ill gladly and desperately take them.
