More 3L problems....Get in here guys.....

[stieny]

Ok, so I am going to make this as clear and short as possible.

I posted up a little while ago about my fuel pump possibly going out after I had some highway hesitation. For reference, see thread here: http://www.therangerstation.com/forums/showthread.php?t=92956.

Well, after a lot of tune up things the heavy hesitation hasn't happened again.

So I went ahead and replaced the fuel pump anyways because I had it and it was old. I was also still getting some very, very slight hesitation/missing.

After I replaced the pump I still have that ever so slight hesitation while at highway speeds. Now I noticed the hesitation after the manifold developed some leaks a little while ago. I was trying to hold off until after winter the replace the manifolds as the leak have gotten progressively worse.

So I drive to work today. Half way through the day I go out to move my truck. I start it up and its popping pretty good under the hood. Now the popping is coming from the leak from the manifold. I can audibly hear this but its much louder then the *tick, tick, tick* that I had before that an exhaust leak sounds like.

So I give it some gas and it revs pretty easy with no hesitation but the popping is random, almost like a miss. I just figure that the leak opened up on me. I go to drive it and the truck is stumbling and missing all over the place. I can hear the leak that now sounds louder and is now popping as the motor is stumbling and missing.

So I have manifolds on order and should be here in the next few days. I pulled off the old manifolds tonight and can see all the leaks that were on both sides. Probably 4 cylinders were leaking.

Over the past few weeks I've replaced plugs, wires, cap, rotor, air filter, fuel filter, fuel pump and flushed the coolant. I also did a compression test on the coolant system. It held steady pressure. I did a compression test on the motor and got about 150 psi on every cylinder.

Now, would all those leaks (with one very large one at the rear drivers side cylinder) cause the motor to stumble and sputter pretty bad? I've also noticed my fuel milage has gone into the crapper as well. I get about 17 mpg @ 90% highway.

Give me your suggestions guys.

 

[Beef52751]

if they get excessive they can cause your O2 sensors to "misread" which may cause your problem. any CEL now???

 

[AgPete139]

Damn. Have you checked voltage at your injectors?

You've gone through the system pretty systematically. Perhaps if one injector is clogged or the system is coming across as lean, it compensates by adding more fuel to another cylinder. It runs rich, and could cause irregular popping like you are describing. Aside from switching out your headers and seeing how they perform afterwards, I would check that. A *tick tick ding* sound is exhaust leak. A *flat flat doosh -engine idle* could be a non-stoich mixture.

The OTHER thing I would assess that fairly easy is the EGR valve. If you can take it off, and physically push in the diaphragm/spring, it's good. As a precaution, you could spray carb cleaner in there, too. This sometimes helps a good deal, as my 5.0L had barely a dumb mumble sometimes after I started it up. Carbon deposits DO accumulate in the greater exhaust system...

That's all I have. Hopefully other experienced techs can pipe in.

Good luck!




Pete

 

[stieny]

if they get excessive they can cause your O2 sensors to "misread" which may cause your problem. any CEL now???

I thought about O2's reading wrong because of a leak but there isn't any CEL's. And it didn't get real bad until today. It was night and day from when I shut it off when I got to work to when I started it up after.

Damn. Have you checked voltage at your injectors?

You've gone through the system pretty systematically. Perhaps if one injector is clogged or the system is coming across as lean, it compensates by adding more fuel to another cylinder. It runs rich, and could cause irregular popping like you are describing. Aside from switching out your headers and seeing how they perform afterwards, I would check that. A *tick tick ding* sound is exhaust leak. A *flat flat doosh -engine idle* could be a non-stoich mixture.

The OTHER thing I would assess that fairly easy is the EGR valve. If you can take it off, and physically push in the diaphragm/spring, it's good. As a precaution, you could spray carb cleaner in there, too. This sometimes helps a good deal, as my 5.0L had barely a dumb mumble sometimes after I started it up. Carbon deposits DO accumulate in the greater exhaust system...

That's all I have. Hopefully other experienced techs can pipe in.

Good luck!



Pete

I thought about the injectors but haven't checked them or went that route yet. I figured that I knew the manifolds needed done so why not try them first. If it is an injector, wouldn't it throw a CEL or lean code? I don't know but it seemed as if the very light hesitation started when I started hearing the leak at the manifolds. Today, with it popping and being a lot louder once I left work, the truck is missing and stumbling 100 times worse then the very faint hesitation that I was feeling on the highway before. So I'm not sure if it's a true miss that I can hear because of the exhaust leak or an exhaust leak getting worse that is causing a miss. But whatever it is, it started happening real bad after I parked the truck today.

Also, the truck came with no EGR from the factory so that is one component that I don't have to check.

 

[stieny]

No one?

I'm about to just sell this thing and pick up something more reliable.

 

[sandulator]

No one?

I'm about to just sell this thing and pick up something more reliable.

I'Ve been having the same problem with my 1992, replaced Pump, regulator,cleaned MAF, Mine will start to die at around 2600-3000 rpm under a load. But if i turn off the key an let it coast for few. it starts right up and runs good for about 30 min... I got a Ford Mechanic coming over this weekend.. Let you know what he finds

 

[Big Jim M]

Fuel filters cause about the same missing! Have you replaced the fuel filter?
Big JIm

 

[AgPete139]

I thought about O2's reading wrong because of a leak but there isn't any CEL's. And it didn't get real bad until today. It was night and day from when I shut it off when I got to work to when I started it up after.




I thought about the injectors but haven't checked them or went that route yet. I figured that I knew the manifolds needed done so why not try them first. If it is an injector, wouldn't it throw a CEL or lean code? I don't know but it seemed as if the very light hesitation started when I started hearing the leak at the manifolds. Today, with it popping and being a lot louder once I left work, the truck is missing and stumbling 100 times worse then the very faint hesitation that I was feeling on the highway before. So I'm not sure if it's a true miss that I can hear because of the exhaust leak or an exhaust leak getting worse that is causing a miss. But whatever it is, it started happening real bad after I parked the truck today.

Also, the truck came with no EGR from the factory so that is one component that I don't have to check.

These trucks are very reliable when treated right. Yours could just be an old truck that wasn't taken care of...

As far as the EGR, I was probably thinking of my mustang.

As far as the CEL, it won't necessarily throw one. With the Distributorless Ignition System, the computer compensates if too many cylinders are lean due to an air leak. My 1st Ranger threw a CEL due to an intake manifold gasket on Bank 1. I replaced that, and everything was gravy afterwards.

Did you actually replace your manifolds with new exhaust gaskets & torque them spec? I'm trying not to sound condescending, but people have put on new heads+gaskets or exhaust gaskets and don't follow the torque pattern steps or apply the right amount of torque (they "feel" it). You should not be getting exhaust leaks with the new manifold you bought.

Also, have you actually gone and pulled the onboard diagnostic code? It's really odd that it has a huge exhaust leak and not throwing a code for your O2 sensors.


Going back to the "hesitation" part of the discussion, the easiest things to check at the MAF & IAC.

MAF sensor = after the intake filter, spray that sensor with carb cleaner like crazy. Seriously, many Rangers suffer from this. The computer cannot get an accurate reading from a dirty/filmy sensor. This would cause the lean/rich/hesitation/crap performance without throwing a CEL code.

IAC = it's on the intake manifold/throttle body, and has two, 10mm screws (IIRC). Take it off, load it with carb cleaner, and allow to dry. There is a moving component in there that adjusts your idle, and often gets gunked up with carbon deposits. This worsens in the wintertime and will also not throw a CEL code.

Seriously, try those. It will most likely help a bit.




Pete

Fuel filters cause about the same missing! Have you replaced the fuel filter?
Big JIm

Yes, he's replaced the fuel filter.

 

[stieny]

Yes, I've replaced the fuel filter. Many times actually over the life of the truck.

As far as care of the vehicle, I was there when it was purchased new in '94. It has spent 90% of its life in a garage. It has always had regular maintenance done to it. IE: oil change every 3k, greased, fluids, filters, plugs and wires and so on.....

And it has a distributor. It is not distributorless. And yes, it had major exhaust leaks at the manifolds and no, there wasn't any cel's nor any stored codes.

I'm putting the new manifolds with gaskets on tonight.

 

[AgPete139]

Stieny, we understand your frustration. We're trying to throw ideas out that could help. We don't have you help you. There's no need to be short or have an agitated tone.

Try the new manifolds, the MAF, and IAC.

We, your readers, have no clue if it was your vehicle that you bought from the showroom floor or not. Most of us bought ours as second hand Rangers.

As far as proper procedures (like torquing), not all newcomers do things correctly.

Be polite, and hope someone helps you.


Just my $0.02.



Pete

 

[Psychopete]

So I give it some gas and it revs pretty easy with no hesitation but the popping is random, almost like a miss. I just figure that the leak opened up on me. I go to drive it and the truck is stumbling and missing all over the place. I can hear the leak that now sounds louder and is now popping as the motor is stumbling and missing.

I had a similar issue with the Tempo engine I pulled out, basically popping and the engine ran like crap. I was surprised that I made it home in the car, but I got a good deal on it. I was in the process of changing the harmonic balancer, so I had most of the FEAD off and couldn't do much diagnostic in fear that I would overheat the engine.

Pass KOEO codes, couple of strange KOER, but the rear main was leaking so I pulled the engine. I also compression tested before pulling and came with with 130~135PSI. Fuel pressure was right on spec.

I changed main bearings, rod bearings, oil pump, water pump,
ect (for good measure), o2 sensor (because I broke it pulling the engine), timing chain (because it was worn to shit), fixed vacuum leaks, cleaned the throttle body, thermostat, put the motor back in and the popping was gone and runs well.

What ultimately fixed it, I don't know, but there were a lot of vacuum leaks and that timing chain was sure loose. But I fixed a majority of the vacuum leaks and still the same behavior when I did the diagnostic tests (but found a couple more once the motor was out). Might be worth while to check the timing chain slack if your engine has a fair amount of miles, mine had 180K.

 

[stieny]

Stieny, we understand your frustration. We're trying to throw ideas out that could help. We don't have you help you. There's no need to be short or have an agitated tone.

Try the new manifolds, the MAF, and IAC.

We, your readers, have no clue if it was your vehicle that you bought from the showroom floor or not. Most of us bought ours as second hand Rangers.

As far as proper procedures (like torquing), not all newcomers do things correctly.

Be polite, and hope someone helps you.


Just my $0.02.



Pete

No, people don't have to help me but I'm not sure why they wouldn't if they know something. Who said I was being short or impolite? I was simply responding to your last post so people know where I stand and what may or may not be on or done to my truck.

As to my actual problem, I got everything buttoned back up and now, no more exhaust leaks but it still is running like crap.

So with it idling I pulled the passenger side center fuel injector wire off. No real change in idle. Put it back on and pull the passenger side rear injector. Engine starts to bog and really miss hard. Plug it back in and pull the passenger front injector wire and it did the same as the rear: started to bog and miss real bad at idle. Back to the center one and pull it: no real change in idle at all.

Also, after closer inspection of the old manifolds, the front and rear runners on the passenger side are pretty black and sooty but the center runner is white as white can be which indicates to me that I have a very weak injector on that cylinder.

So now I'm leaning towards throwing in a set of injectors as they may be the cause to all this headache.

 

[kimcrwbr1]

Are you resetting the computer every time you mess with a sensor it will never run right running on old values. disconnect the batt for 1/2 hour and then drive it for at least 20 minutes. My big thing lately is the PCV dont check or clean it just get a new one when you change plugs or at least plug wires.

 

[stieny]

Are you resetting the computer every time you mess with a sensor it will never run right running on old values. disconnect the batt for 1/2 hour and then drive it for at least 20 minutes. My big thing lately is the PCV dont check or clean it just get a new one when you change plugs or at least plug wires.

Well, being OBD I, I don't know if that necessarily applies to me. Also, I haven't changed any sensors just yet. Its been all tune up stuff thus far but thanks for the suggestion.

 

[barrys]

If I'm telling you a bunch of stuff you already know, then please excuse me in advance...

> being OBD I, I don't know if that necessarily applies to me
OBD I definitely goes through a learning cycle, so pulling the battery to reset and going on a learning drive could not hurt.

> So with it idling I pulled the passenger side center fuel injector wire off. No real change in idle.
With your OBD tester or equivalent (paper clip, test probe, or meter), you can do repeated "cylinder balance" tests with increasing sensitivity to measurements with seqeuntial tests. If you have one cylinder that's causing obvious problems, this might give clues. This is only testing at idle so it can't tell you what's going on at high RPM.

Before resetting, I would do a KOEO self test and see if there are any "continuous" codes in memory. Note that only very few codes will turn on the CEL on an OBD I system. You'll have to do a KOER test to get to the cylinder balance test. You can choose to do it carefully and capture the codes or just blow through it and ignore the codes.