First post..

I bought this truck about a little over a month. 1998 Ford Ranger 2.5L Automatic. I believe its a XL no emblems to know what it is... Title just say Ranger no submodel.

List of items replaced:
Engine oil/filter
manifold gasket / cleaned manifold.
pcv
spark plug wires
spark plugs
air filter
EGR Valve
DPFE
Fuel Filter
Front brakes and rotors replaced
all 4 tires

Ok let me start by saying when I finally had it home It gave me a EGR code. Got it fixed then I got a 02 Sensor code after I fixed the EGR. But as soon as it came it went away.

So when the truck is started Hot/Cold doesn't matter it starts off real rough like it wants to stall but the rpms pick up and the engine starts to act normal. Driving or stopped the truck will all of a sudden drop rpms and feel like its going to stall. Recovers and continues.

Driving on flat surface works just fine. No Issue but as soon as there is a incline the truck starts to lose power. Speed drops and rpms go high I don't have a tach with rpms reading but I can hear the engine working overtime. Also the transmission drops gear. I have let go of the gas and gassed it again and the truck will go up a gear and as soon as it jumps to the following gear it goes back down. I have felt at 2 different times that the engine just gave up and got back to working all of a sudden.

Also for some reason every time the truck changes gear there is a rattling noise. Which to me sounds like rice krispies. it goes away as the truck picks up speed in that gear but as soon as it changes gears I hear it again and it goes away. It only makes that noise when im pressing the gas. If i let go the noise goes away, While I'm on Drive. If I press the gas and its on park it makes no noise.

Took it to a transmission shop to see if it was the transmission making all that noise they said it wasn't that.... So I don't know what else it could be. I got under the vehicle and the cat look fairly new. Also when I first got this truck the registration on this vehicle was from 2016... So i feel like this truck sat for a while. When I changed the oil, it had a distinct smell of fuel. I have yet to check if the new oil smells like fuel. Also added seafoam in the gas tank. Sitting at half a tank.

I got no history on this truck. Tried contacting the person I bought it from and got ignored.... Not a good sign.


Thank you for reading my long journey trying to resolve this issue.
-CC
Central Texas

 

You purchased a used truck with no service history, this will give you an opportunity to check the truck over front to rear top to bottom.

I am positive you will find more than a few problems that need to be addressed, I would start with the inspection.

The noise your hearing may be u-joints, I would pull the driveshaft and inspect them.

Sounds like the transmission may be slipping, I would inspect the transmission fluid to make sure the fluid is not burnt looking or smelling and the fluid is at the correct level reading both sides of the dip stick.

 

Welcome to the forum

+1 to the above

Also "rice krispies" noise could be pinging/knocking noise made by gasoline pre-igniting in the cylinders.
This noise usually occurs when engine is put under any load, i.e. gas pedal pushed down
It is caused by many things
Lean fuel condition
Low EGR flow
Carbon build up inside cylinders
Spark advance problem
Bad gasoline, too much water or octane too low

1998 Ranger has spark control in the PCM(computer) so no adjustment available
1998 Fuel pressure should be 60-65PSI when engine is running, 50psi engine off, 1998 is first year of this High Pressure system, 1997 and earlier used 35psi
Lower fuel pressure will cause Lean condition that PCM can't over come instantly on acceleration but will adjust for it after a few seconds.
So Pinging would be brief but consistent under same conditions
You can rent fuel pressure gauge, or "loan it" from most auto parts stores, its a black and white test so good to do, you either have good fuel pressure or you don't

You replaced EGR valve so I assume EGR tube to exhaust manifold was clear, no build up, so that can be taken off the table

Carbon build up is harder to check for, older spark plugs should have given signs of possible build up, blackish residue on the tips.
If you run Seafoam, or similar injection cleaner, in the gas tank a few times this can clean injector tips and also loosen and blow out some carbon build up.
Dirty injector tips can cause momentary Lean condition as well, they Drip Fuel instead of spraying it at lower RPMs, i.e. idle, this can cause stumbling idle and lean condition(pinging)

IAC(idle air control) valve can be cleaned, just a couple of bolts to remove it

Thread with pictures here: How to: IAC valve cleaning thread (w/pics) | Ford Explorer and Ford Ranger Forums - Serious Explorations

Your 2.5l will look a little different but is the same unit
The PCM uses the IAC Valve to set air flow at idle, if it is sticking then rpms will drop until PCM can "unstick it" and reset its position for "target" idle RPMs
It is just a sliding valve solenoid, it can get dirty inside so "sliding" part sticks a bit


2.5l is a Lima engine, same engine as 2.3l used in Rangers until 1997, same head, block, pistons, valves and cam, just longer stroke
These engines used timing belts, the belts can stretch and do need to be replaced every 80-100k miles, not hard to do, but can cause lower power overall if timing is not spot on
No engine damage will occur if timing belt breaks

 

great info!! Today I started to get the belts replaced but I started of the day pretty great. broke my phone and the radiator on the truck. Couldn't get the top hose off and I tried twisting it off and I twisted off the entire section where the hose was attached to. so I went to look for the part no luck. everything is special order. so now I'm stuck waiting on parts.

also can I move the crankshaft pulley to match the pulleys to the markings to make sure the timing is correct?

I will check the u-joints on it.

 

Sorry about your phone and radiator, i cannot stress this enough do not spend any money on this truck until you know for sure everything this truck is going to need by doing a complete inspection.

The last thing you need is to dump a lot of money into this truck to find out that it needs major repairs that makes the truck not worth the repair or worse spend money on parts that could have waited till later and not have the cash or time needed to repair the important items on your list.

 

Yes you can remove a round inspection plug to see the Cam's triangle timing mark.
And yes the crank pulley would be on 0 deg TDC when triangles are aligned, meaning good cam/crank timing

Crank turns TWO TIMES for each one revolution of Cam, 4 stroke engine, so Cam mark may not be visible when crank pulley is at TDC, turn crank one full revolution and Cam mark should now be visible and you can check the timing.

 

Before i bought my truck it was sitting for 9 months. After a year of driving i can say this... Really check everything out! Boots on joints and bushings especially. My sway bar bushings were fine when i bought it, but now they squeak and groan badly. (a little liquid wrench fixes a lot lol). Your truck might be a retired public works truck if its white. In that case REALLY check everything out. Mine was a city truck and they didnt take care of it at all :(