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HDGENE
HDGENE, Ford Senior Master/Diesel/Trans
Category: Ford
Satisfied Customers: 4784
Experience:  25 years Auto experience, Ford ,GM, Chrysler, Asian & European
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2002 Ford ranger power loss when cold. Won't drive fast at

Customer Question

2002 Ford ranger power loss when cold. Won't drive fast at low rpms. Also after driving for a few minutes all of a sudden its like a switch clicks on and bam power back to normal. What could cause this
Submitted: 1 year ago.
Category: Ford
Expert:  HDGENE replied 1 year ago.

Hello, what engine is in this ranger a 3.0 or 4.0 SOHC or OHV motor? How many miles are on the engine? Are any warning lights on?Check engine light? Does it start up normally since you have an issue when cold?

Customer: replied 1 year ago.
2002 and I have the 3.0 engine. I have 170k but engine was rebuilt around 20kk ago. Starting is no issue everything is fine but then I drive and it is OK ubtill I really give it some gas and then you notice the problem and it goes away after driving a few miles.
Customer: replied 1 year ago.
All of a sudden it just bam power is back and its all fine. It seems been doing this now that colder temps outside
Expert:  HDGENE replied 1 year ago.

Ok a lack of power can be an issue with a weak fuel pump.If the fuel filter hasn't been changed in awhile I would replace that first and see if it helps. A fuel pressure test would help tell if its a fuel pressure issue when the vehicle exhibits a lack of power. A diagnostic check for codes would alaso tell if its possibly storing any lean codes which could be an indication of possible low fuel pressure

Customer: replied 1 year ago.
A buddy with a ob2 scan ran it and I did have lean codes I don't remember which codes they were
Expert:  HDGENE replied 1 year ago.

P0171/P0174 would indicate both banks lean, this would be caused by an issue with a vacuum leak,mass airflow sensor or loss of fuel pressure

Customer: replied 1 year ago.
Would a fuel pump be affected by engine being cold and then all of a sudden change and be OK once warm
Expert:  HDGENE replied 1 year ago.

It Is possible, usually its more when they are hot and run for awhile they have issues, engine coolant temperature sensor can also be giving a false reading but it sounds more like its running low on fuel pressure. Drive the truck with a fuel gauge installed and if it drops, its a weak pumo

Customer: replied 1 year ago.
I'm gunna start with what u said and go from there. This is the fist I used this site. If I need to talk to you again how can I find you on this site?
Expert:  HDGENE replied 1 year ago.

Just respond back to this question you started and I can assist you further. The question remains open until it is rated and you hit accept and I can follow up more if needed from there as well

Customer: replied 1 year ago.
Is there a time limit I have to keep this topic open?
Expert:  HDGENE replied 1 year ago.

Nope, long as you keep responding to the question from time to time it will remain open. I don't get paid for assisting you until you rate and hit accept

Customer: replied 1 year ago.
Sounds good. Going to look into this tomorrow when it's daylight and you have been great so far extremely appreciate your knowlege
Expert:  HDGENE replied 1 year ago.

You are welcome,just respond back when you have more info

Expert:  HDGENE replied 1 year ago.

Hello do you need more help with this concern

Customer: replied 11 months ago.
Hey so I got a obd scan tool and I had it on when driving and right when my truck goes from open loop to closed loop is when it starts running perfectly fine. Is there any recommendations of what it could be ?
Expert:  HDGENE replied 11 months ago.

Hello, what engine is in the ranger? No codes stored or check engine light on? Idles ok just no power? how many miles and any major repairs done prior to having this concern?

Customer: replied 11 months ago.
3.0 v6 2002 and 170k n mybmotor was rebuilt like 20k ago n no major repairs since its been fine till now. And it idles fine just when it's still code and in open loop runs almost like its got no power when the engine is under load
Customer: replied 11 months ago.
Then once closed loop is on instant power back to normal
Customer: replied 11 months ago.
Code 301 and 305
Expert:  HDGENE replied 11 months ago.

Ok so you have misfire codes for cylinders 1 & 5. When the engine was rebuilt, did it have a valve job done? Is it misfiring when it has a lack of power?

Customer: replied 11 months ago.
Not that I can tell.
Customer: replied 11 months ago.
it got new valves. The only thing I switches since was top radiotor hose and also thermostat. I also noticed my truck temp gauge stays under half where before it seemed a little higher?
Expert:  HDGENE replied 11 months ago.

Ok i was asking about the valves because they had issues with the valve seats causing random misfire codes, if you clear these codes and they come back, something is going on with that which would need to be checked further.They also had issues with both the ignition coil and fuel injector flow. If you used an aftermarket thermostat that may be why the engine is running cooler, different temperature range thermostat. Hard to say what else would cause a cold issue. It should change from open to closed loop very quickyl,even before the engine is warmed up fully unless its the wrong thermostat but still it shouldnt have a lack of power.Id clear the misfire codes and see if they return first

Customer: replied 11 months ago.
I will clear the codes and go for a drive. In the morning time say I start my truck and let it idle for 10 min it takes about 10 min of driving to change out of open loop mode. If that helps you at all.
Expert:  HDGENE replied 11 months ago.

Yes,too long, if the temp gauge is low, it should eventually set a P0128 code saying its taking too long for the engine to reach normal operating temperature, so if you didnt use a ford thermostat you may want to change it out and see if that helps.

Customer: replied 11 months ago.
I just got one from. Auto zone. What brand should I get. And like right now its fairly warm out I started my trucks it was idling sort of low. But changed to closed loop like withina min or 2 just sitting here while I switched the codes off
Expert:  HDGENE replied 11 months ago.

Ford/Motorcraft part from dealer way to go.

Customer: replied 10 months ago.
Trouble Code Triggering Freeze Frame:
P0351: Ignition Coil "A" Primary Control Circuit/Open
Freeze Frame Data:
• PID : Description : Value
• 03 : Fuel System Status : Open loop due to system failure
• 04 : Calculated Engine Load Value : 78.4 %
• 05 : Engine Coolant Temperature : 71 °C, 160 °F
• 06 : Short Term Fuel Trim Bank 1 : -9.4 %
• 07 : Long Term Fuel Trim Bank 1 : 1.6 %
• 08 : Short Term Fuel Trim Bank 2 : -9.4 %
• 09 : Long Term Fuel Trim Bank 2 : 1.6 %
• 0C : Engine RPM : 1776 rpm
• 0D : Vehicle Speed : 30 km/h, 19 MP
Expert:  HDGENE replied 10 months ago.

Hello, does it feel like a misfire since it is saying it has a misfire on cylinder #1? What enigne is in the ranger and how many miles? Does the check engine light flash while driving an it acting up? Original plugs, wires, coil?

Customer: replied 10 months ago.
3.0 v6 2002 and 170k n mybmotor was rebuilt like 20k ago n no major repairs since its been fine till now. And it idles fine just when it's still code and in open loop runs almost like its got no power when the engine is under load
19 December 2015 11:04 Then once closed loop is on instant power back to normal
19 December 2015 11:05 Code 301 and 305
Expert:  HDGENE replied 10 months ago.

Ok when the engine was repaired did it have valve work done. No other codes key on engine off, key on engine ruuning? Does the P0301 code come back if cleared? Snapshot data looks normal

Customer: replied 10 months ago.
Yeah pretty sure valve job was done and what do you mean key on etc sorry im a newb lol but yeah clear code n comes back and when cold or first startup sluggiah really bad and stays in open loop for a lobg time
Expert:  HDGENE replied 10 months ago.

Does it run rough at idle when cold until it runs a few then clears up? Pulling memory codes is on test. Doing on demand tests Key On Engine Off and Key on engine running tests check everything now, memory codes are codes that set while driving.

Expert:  HDGENE replied 10 months ago.

Two common issues,besides valvework. With the P0351 code it can be an issue with a bad or weak coil, or an issue with the coild driver from the PCM to ground the coil to fire. The other issue is a fuel injector leaking down causing a misfire on cold startup or after sitting awhile and flooding a cylinder