1990 Ranger, Pulsing Engine
Thread Starter
|
Trailering
Joined: Apr 2009
Posts: 16
Likes: 0
From: https://t.me/pump_upp
1990 Ranger, Pulsing Engine
I have a 1990 Ranger, 2 WD, Auto, 2.9 L.
I have been having issues with the engine running very rough, finally replaced the check valve, and today replaced the power brake booster.
The truck was pulsing at idle, almost stalling, and would have a small seizure at 50 to 60 mph. My gas mileage went down to about 12.3 to 13, depending on where I went. It would also smoke really bad at start-up and smelled like gasoline when I got out of the truck.
I previously changed the fuel filter, the spark plugs, the wires and now the power brake booster. This seemed to work at first.
It started with almost no smoke, had power at acceleration, didn't pulate at idle and didn't have the seizure at 50 - 60.
Now, I went for another ride and it began to pulsate at idle again. Can anyone help?
I have been having issues with the engine running very rough, finally replaced the check valve, and today replaced the power brake booster.
The truck was pulsing at idle, almost stalling, and would have a small seizure at 50 to 60 mph. My gas mileage went down to about 12.3 to 13, depending on where I went. It would also smoke really bad at start-up and smelled like gasoline when I got out of the truck.
I previously changed the fuel filter, the spark plugs, the wires and now the power brake booster. This seemed to work at first.
It started with almost no smoke, had power at acceleration, didn't pulate at idle and didn't have the seizure at 50 - 60.
Now, I went for another ride and it began to pulsate at idle again. Can anyone help?
Post Fiend
Joined: Jan 2003
Posts: 9,748
Likes: 16
From: Connecticut
Thread Starter
|
Trailering
Joined: Apr 2009
Posts: 16
Likes: 0
From: https://t.me/pump_upp
I haven't gotten any, the last time I had someone scan it, it was running lean. My check engine lite has never come on and no one at autozone knows how to read the scanner.
Logistics Pro
Joined: Jan 2002
Posts: 4,907
Likes: 39
From: suburban atlanta
A fuel pressure regulator won't throw codes by itself, but can cause too much fuel to flow, bad idle and fouled spark plugs. You would have to use a pressure gauge to measure the pressure with and without the vacuum line connected. I believe yours has a vacuum modulated pressure regulator, which will bump the pressure when you step on the accelerator pedal. If you remove the vacuum line and find gasoline, you need a new regulator.
Oh, and check the air filter.
tom
Oh, and check the air filter.
tom
Thread Starter
|
Trailering
Joined: Apr 2009
Posts: 16
Likes: 0
From: https://t.me/pump_upp
I know there is gas in the vacuum lines.
My power brake booster just blew again and now it sounds as if something is loose under the drivers side. Can't find anything loose, though.
Does anyone know where I might find the MAP or the FPR? I don't mind getting them, but would like to know what and where they are first.
Thanks everyone.
My power brake booster just blew again and now it sounds as if something is loose under the drivers side. Can't find anything loose, though.
Does anyone know where I might find the MAP or the FPR? I don't mind getting them, but would like to know what and where they are first.
Thanks everyone.
Trending Topics
Logistics Pro
Joined: Jan 2002
Posts: 4,907
Likes: 39
From: suburban atlanta
*IF* you have a MAP, it is a box about the size of a deck of cards with a vacuum line to the intake manifold and 3(?) wires that lead back to the ECM. More likely you have a MAF, which is just after the air filter in the plastic intake tube leading to the throttle.
Both are methods to measure vacuum or air flow, indicating load on the engine. The MAP will lead to crappy idle, the MAF shows more as chugging or hesitancy accelerating.
If you have fuel in the vacuum lines, something is leaking that shouldn't. Did you check the vacuum line to the fuel pressure regulator? If you find fuel there, you likely have found your problem. It is easy to do, and a definitive test. Where else could you get gas in the vacuum line, eh?
If you are replacing the power brake booster because it is getting blown up, why not fix the cause of it getting blown up?
tom
Both are methods to measure vacuum or air flow, indicating load on the engine. The MAP will lead to crappy idle, the MAF shows more as chugging or hesitancy accelerating.
If you have fuel in the vacuum lines, something is leaking that shouldn't. Did you check the vacuum line to the fuel pressure regulator? If you find fuel there, you likely have found your problem. It is easy to do, and a definitive test. Where else could you get gas in the vacuum line, eh?
If you are replacing the power brake booster because it is getting blown up, why not fix the cause of it getting blown up?
tom
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Elder User
Joined: Jan 2004
Posts: 537
Likes: 0
From: Yes
The FPR is on the fuel rail. On your truck, it would be on the drivers side rail, toward the back. It's a small can-shaped piece with a vacuum line going in the top. There are 3 screws in a triangular shape that attatch it to the rail. If in doubt, follow the fuel line up from the frame rail to the engine, at some point it will couple to the fuel rail. From there, search till you find it. If you have fuel in the vacuum lines, you have probably just condemned the FPR. They aren't very expensive, and have a limited life anyway, so it might not be a bad place to start. The MAP/MAF (not sure that the 2.9l ever had a MAF) is much more expensive, and difficult to test, so it may be a last resort to fix. The Oxygen sensor is another service item that can cause what you describe, but I still say start with the FPR.
Elder User
Joined: Jan 2004
Posts: 537
Likes: 0
From: Yes
I wasn't disputing the MAF equipped 2.9l, I simply can't remember if there ever was one or not. I had an '88 and it had a MAP, but all the other rangers I've had over the years have had 4 bangers. I thought I remembered reading that the 2.9l was always equipped with a MAP sensor, but who knows. In any case, I certainly can't be sure enough to correct you about something that trivial, just thinking out loud really.
Thread Starter
|
Trailering
Joined: Apr 2009
Posts: 16
Likes: 0
From: https://t.me/pump_upp
Ok, so I changed the FRP and replaced my power booster. It seems to run good. I had disconnected the battery overnight and then went through all of the gears to let it relearn correct idle. (Saw this in another thread on here). It seems to run good, some white smoke at startup and cold idle, but good power and start from stop.
We'll see, the other power booster lasted 2 days, we'll see what happens today I guess.
Thank you everyone for the awesome advice.
We'll see, the other power booster lasted 2 days, we'll see what happens today I guess.
Thank you everyone for the awesome advice.
Thread
Thread Starter
Forum
Replies
Last Post
wilfreeman
Brakes, Steering, Suspension, Tires, & Wheels
20
Apr 5, 2016 10:13 PM
Chris0611
1999 - 2003 7.3L Power Stroke Diesel
3
Sep 27, 2014 10:28 PM
bmoran4
1948 - 1956 F1, F100 & Larger F-Series Trucks
8
Aug 4, 2014 02:28 PM
GB SISSON
1948 - 1956 F1, F100 & Larger F-Series Trucks
16
Mar 13, 2014 09:12 PM