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Engine struggles up hill

3K views 28 replies 6 participants last post by  ChryslerTC1986 
#1 ·
Morning everybody, So recently on my 1986 LeBaron 2.5L non-turbo engine I have noticed a sufficient loss in performance. My first thought was transmission, but then I started to hear what sounded like a tincan rattling with BBs in it when I put the car underload or when the car has to downshift going up hills. My mph are horrible now. I've never really heard what engine knock actually sounds like but I'm assuming what I'm hearing is the engine pinging

I cant for the life of me figure out exactly what the problem is but here my thoughts:

-bad fuel filter?
-low compression?
-slipping tranny?

The fuel filter is definitely original, I'm looking to change this today. What's the best way to depressurized this system?

otherwise, I'm stumped..
 
#2 ·
#3 ·
hmmm.. I do know right off the bat that the cat converter is definitely busted. it rattles (not heat shield) and seems to effect the engine. but it's been like that since I got the car (hasn't been a high priority fix) and the engine issue just started a week ago..
 
#4 ·
Your cat either died enough to turn the catalyst sideways or you lost cam timing on s loose belt. Should get rid of the cat and add a 2 1/4 exhaust on it. Next is fuel which is a pain as you'll need to see the pressure under a load. The filter is a given. But s sudden not on going lose is different. Pump died, skipped a tooth, cat flipped. That type of thing. Filter is a gradual loss.
 
#5 ·
Hmm.. Naj, by the sounds/looks of it this whole cam timing scenario seems daunting.. possible for a novice mechanic to do?

Also, Mr. Pope, this whole concern with testing fuel pressure under load -- why do you say it is a PITA?


I lack my manual at the moment so care to explain the best procedure for:
-diagnosing Cam timing?
-testing fuel pressure underload

The cat swap for a section of 2 1/4" exhaust seems relatively straight forward.

Also... what?:

But s sudden not on going lose is different.
?? lol :laugh2:
 
#6 ·
1)You stated that this is a 2.5L TBI car and Pope may think this is a turbo car, 2 1/4" exhaust is not going to really do anything for a TBI car, which would also explain why he mentioned fuel pressure under load, on a turbo car rail pressure changes constantly as engine vacuum/pressure changes, on a TBI car pressure remains constant under all driving/load conditions, however...
Since your driveabilty issue is under load it is a good idea to check fuel pressure under load to be absolutely sure.

2)To check fuel pressure under load you would need to connect the fuel pressure gauge underhood at the TBI fuel inlet and run the gauge out from underhood and tape the gauge to the windshield and go for a ride (with a helper) and drive under the conditions where the problem is present and see if fuel pressure drops.

3)Cam Timing on the 2.2L/2.5L engines can be done by a Novice and is really not that difficult, gaining access is all nuts and bolts, aligning the marks properly make take a few tries to get it correct, we have all been there.
Also, the 2.2L/2.5L engines are non-interference engines so no worries there.
Checking Cam Timing is relatively simple.
1)Disconnect and isolate the - battery cable.
2)Remove the upper timing cover
(2 nuts on the valve cover and 1 bolt where the upper cover meets the lower cover)
(Inspect the belt for missing teeth while the cover is off)
3)Remove all 4 spark plugs.
4)Bring the piston on #1 cylinder to TDC on a compression stroke (distributor rotor pointing to #1 cylinder on the distributor cap.
5)Align the mark on the bellhousing timing marker with "0".
6)Check to see if the Cam sprocket is at the 12 o'clock position with the cylinder head.
This is the tricky part, the cylinder head is on an angle so the mark will not be 12-6. it will be close to 11-5.
(See the illustrations, if you are not sure take a pic)

4)Over the years I have seen strange things with cars, although you have been driving with no issues until recently if the Cat got worse it could be moving and blocking the exhaust when going up hill (Gravity), I have also seen foreign objects in fuel tanks that caused a problem when it moved to a certain position(we found a bee in the fuel tank of a Ford Truck that caused problems when turning).
The only way to find the cause of your issue is diagnose all of the systems and eliminate them as the cause, there are no shortcuts, if you say "it can't be that so I am just going to assume it is good and move on" you may have just bypassed your problem and then you will "be in so far you cannot see the forest for the trees", Been There, Done That!!!

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Auto part Engine Fuel line Vehicle Car


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#9 ·
4)Bring the piston on #1 cylinder to TDC on a compression stroke (distributor rotor pointing to #1 cylinder on the distributor cap.

5)Align the mark on the bellhousing timing marker with "0".

6)Check to see if the Cam sprocket is at the 12 o'clock position with the cylinder head.
4) How exactly does one "bring the piston to TDC"?
5) How exactly does one "align the mark..."?
6) Is this a visual "check"? or some other kind of check

tomorrow is likely I'll check fuel pressure.

Attached is the walkthrough on testing fuel pressure from my Haynes manual. Any objections to how this is described? the spec on pressure is 36psi for 1984 through 1986 single point 2.5L engines.
 

Attachments

#8 ·
You did mention that it was a TBI car in your opening sentence.

"my 1986 LeBaron 2.5L non-turbo engine"

Not saying he did but sometimes we tend to read right past those things, we all do it.
 
#10 ·
To bring the piston to TDC on a compression stroke you need to remove the spark plugs and then use a socket and ratchet on the crankshaft nut to turn the crankshaft clockwise until the piston is at the top of its stroke, then you align the mark on the flywheel with 0 on the timing window marker but slowly moving the crankshaft until the marks align and you are at top dead center.

The easiest way to be sure you are on a compression stroke is to place your thumb over the open spark plug hole for #1 cylinder and have a helper just "tap" the key until you feel the air push on your thumb, you are now on a compression stroke, follow the instructions above.
(Be careful of the ignition wires do not get shocked, I would recommend just removing the distributor cap and wires and placing it out of the way.)

Your Haynes manual is incorrect, AFAIK Chrysler only used high pressure TBI in 84/85 and switched to low pressure TBI in 86.

This is from Donavans Dodge Garage
1984-1985
"The first two years of TBI FI used a single high pressure (36 psi) injector mounted in a throttle body, "slider" camshaft and fairly crude electronics. The 1984 year had oddball "stud" connectors for the coolant sensor which was done away with in 1985. 1985 introduced the GM style weatherpak connectors for the sensors which are still in use to this day. Logic modules & power modules between 84 and 85 are not interchangeable. Headbolt fastener size is 10 mm for the 84-85 model year."

1986-1988
"1986 introduced the new low pressure (15 psi), low profile TBI FI setup."

The Dodge Garage
Scroll to EFI Database and click on it, go to Overview.

Just some friendly advice...
Dump the Haynes Manual and invest in the FSM's (Factory Service Manuals).
You can find them used on eBay.

https://www.ebay.com/itm/1986-Servi...818332?hash=item48d20e9cdc:g:GBYAAOSw5e5ddfw8
 
#11 · (Edited)
I went ahead and bought those manuals. definitely a good call thanks for the link

been in the process of hooking up the fuel pressure gauge to test today. replace the lines because they were old. then I found a hose which wasn't connected to anything, by my deduction it looks like a purge hose. do you know where that goes? Is it supposed to hook up to anything? the hose look like it was connected to throttle body down to the left of the return fuel line.

I attached a few pictures plus the vac diagram in case that helps.
 

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#12 ·
scratch that previous message. I figured it out.

did my fuel pressure test. floated around 14 PSI -- drifted only slightly down to just above 12 psi but never lower. so I assume that is okay, even when It was under load.

I think my next best bet is to take care of the cat
 
#13 ·
The spec is 14-16 so 12 is slightly low, however we do not know the accuracy of the gauge you were using.

As long as fuel pressure remained constant when under load with the problem present then you can safely remove fuel pressure from the list as a cause, however...

Just to err on the side of caution...
If the fuel filter is old or you do not know its age you should probably replace it.
Also, did you replace the fuel lines under the car as well as underhood?
 
#14 ·
yeah it seemed to me the gauge moved mainly due to bumps while driving. The gauge went in intervals of 2 (4 tick marks between each whole number 0||||10||||20||||etc.) so not the most accurate yet still decent enough to get a reading. I replaced the fuel filter prior to testing. the only lines I changed were the fuel hoses by filter and throttle body. I haven't tried replaced any metal lines. the lines running from tank to underhood are as flaky as baklava with corrosion. They most likely should be changed, as much as I would love to be the one to do so I have neither the time nor understanding as to how to do so.
 
#20 ·
I haven't tried replaced any metal lines. the lines running from tank to underhood are as flaky as baklava with corrosion. They most likely should be changed, as much as I would love to be the one to do so I have neither the time nor understanding as to how to do so.
As long as the metal lines are not leaking or crumbling when touched the rust is probably surface rust only.
You do have two rubber lines coming off of the tank that you did not mention you replaced.

I think it's safe to say it should be replaced or deleted . ever since I've owned the wagon there has been a rattle in there.

I did find this magnaflow:

https://shop.redline360.com/product...kdSdZJfNj8GiU2khcxNkEtCHEHLqd6ABoCZ1wQAvD_BwE
That is the correct Magnaflow cat for your vehicle according to the Magnaflow catalog.

https://www.magnaflow.com/collections/catalytic-converters

as for my TBI I'm under the assumption that deleting the cat is the same thing as replacing it. despite the emissions which are null and void for my car's year.
You can take the front pipe down and gut the Cat just to see if the problem goes away.
You can also cut the old cat out of the pipe and install a Universal Cat, you just cut the pipe before and after the Cat and use exhaust clamps on the new one.
You can rent a Pipe Cutter at AZ, you just leave a deposit on the tool that is fully refunded when you return it.

https://www.autozone.com/loan-a-too...3-4-in-to-3-1-4-in-tailpipe-cutter/111609_0_0

Having said all of that I also have to say this...
Deleting or Gutting the Cat is an option however even if your state does not do emissions testing on older vehicles it is still a Federal Offense to Delete or Gut the Catalytic Converter with fines up to $10,000.00.
Now of course that may only happen if you get caught, here is the question I ask myself in situations like this...
Even though the chances are Extremely Slim that I will get caught, it only takes one time, Can I Afford That One Time?
In N.J. all vehicles 1995 and older are exempt from State Inspection however...
The Local Municipalities use State Mobile Inspection Vehicles and set up check points and if you have an expired inspection sticker, your car seems to be running poorly or you have an older vehicle without an inspection sticker you will be asked to pull your vehicle over and have your vehicle checked.
What state are you in?
Apparently Maine recently increased their emission standards.

My advice would be to do a compression check. There are a lot of variables to consider, but a compression check would make sure that you do not have any burnt valves or broken piston rings. My '88 Dodge Turbo Lancer is in the middle of a rebuild right now because the compression went down to 60 psi. in almost every cylinder. The glaze on the cylinder walls reduced compression significantly at just over 200,000 miles. It is hard to know exactly because the odometer quite working. I have also had the cat bust up and clog the muffler, another real performance killer. A good muffler shop can drill a tiny hole and check the pressure in the exhaust pipe. Do not take the car to just any muffler shop, because the price can vary greatly. Another idea is to check the MAP sensor. If it goes bad, the motor will go into limp-in mode.
Just so we do not confuse the OP...
1)A burnt valve or loss of compression will create a misfire that will be present all of the time and that misfire would probably get worse under load.
There is no misfire on this vehicle, just a loss of power under severe load.
If the timing belt jumped that will cause compression to be lowered on All Cylinders and the OP was informed he needed to verify Cam Timing.

2)An issue with the Map Sensor Circuit that puts the car in "Limp In Mode" would also illuminate the Power Loss/Check Engine Light which is not an issue on this car.

3)The OP can test backpressure himself instead of paying someone.
Thexton makes the kit you are referring to or you can buy the adapter that threads in where the O2 Sensor is located and connect your Vacuum/Pressure gauge to it, that is what I have, came from Snap-On years ago.

https://www.tooltopia.com/tool-aid-33600.aspx

https://www.amazon.com/Thexton-389-Backpressure-Test-Adapter/dp/B0018LN2DC
(You have to use your own Vacuum/Pressure Gauge when using the Thexton Kit)
 
#15 ·
I would get the catalytic converter checked. I had a 1987 Horizon with the 2.2L carbureted engine, the converter on it disintegrated and it would periodically not get out of it's own way. Turned out a large chunk would get across the outlet and block it. A new converter solved the problem.
 
#16 ·
I think it's safe to say it should be replaced or deleted . ever since I've owned the wagon there has been a rattle in there, I think i just got use to it and started focusing on other issues.. I took a peek on RockAuto for a direct fit cat and they are "temporarily out of stock" so who knows how long they will be back in stock. partsgeek doesn't have any direct fit as far as I could find. I can't weld. What do you suggest? DIY or have a shop deal with it

I did find this magnaflow:

https://shop.redline360.com/product...kdSdZJfNj8GiU2khcxNkEtCHEHLqd6ABoCZ1wQAvD_BwE
 
#17 ·
Naj and others may know better than I, but could you delete the cat? Even if you do it just to prove it is it or not? I understand you would not pass emmisions testing and I do not know if you still need to do that. On my Turbo I do not plan to run a cat. Just thinking out loud.
 
#19 ·
My advice would be to do a compression check. There are a lot of variables to consider, but a compression check would make sure that you do not have any burnt valves or broken piston rings. My '88 Dodge Turbo Lancer is in the middle of a rebuild right now because the compression went down to 60 psi. in almost every cylinder. The glaze on the cylinder walls reduced compression significantly at just over 200,000 miles. It is hard to know exactly because the odometer quite working. I have also had the cat bust up and clog the muffler, another real performance killer. A good muffler shop can drill a tiny hole and check the pressure in the exhaust pipe. Do not take the car to just any muffler shop, because the price can vary greatly. Another idea is to check the MAP sensor. If it goes bad, the motor will go into limp-in mode.
 
#22 ·
Installing a Universal Cat is perfectly fine and Legal, permanent repair as long as you have a Cat approved for the state you live in.

California, New York and Maine have more stringent emission standards and Cats are made just for those states, all other states are Federal.

I installed a universal cat on my car and that is usually what exhaust shops install except they weld it in rather than using clamps.

RUNNING A COMPRESSION TEST
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#23 · (Edited)
Ran compression test.

I took videos so feel free to review if you like:

Dry Comp Test (1-2-3-4) :
[ame]https://vimeo.com/369946034[/ame]

.

Wet Comp Test (1-2-3-4) :
[ame]https://vimeo.com/369945834[/ame]

Results are as follows:

Dry test
Cylinder#1 = ~110 psi
Cylinder#2 = ~95 psi
Cylinder#3 = 120 psi
Cylinder#4 = 120 psi
------------------------------
Wet test
Cylinder#1 = ~110 psi
Cylinder#2 = ~90 psi
Cylinder#3 = 120 psi
Cylinder#4 = 120 psi

Now i realized after I ran this test that my engine was not at operating temperature. Not sure how much of an influential factor that is but I thought I would mention it.

It seems like Cylinder#2 is low in compression. ?

Does this indicate a bad exhaust valve?

I'm going to do a cat swap today if the weather permits.
 
#24 ·
Ran compression test.

I took videos so feel free to review if you like:

Dry Comp Test (1-2-3-4) :
https://vimeo.com/369946034

.

Wet Comp Test (1-2-3-4) :
https://vimeo.com/369945834

Results are as follows:

Dry test
Cylinder#1 = ~110 psi
Cylinder#2 = ~95 psi
Cylinder#3 = 120 psi
Cylinder#4 = 120 psi
------------------------------
Wet test
Cylinder#1 = ~110 psi
Cylinder#2 = ~90 psi
Cylinder#3 = 120 psi
Cylinder#4 = 120 psi

Now i realized after I ran this test that my engine was not at operating temperature. Not sure how much of an influential factor that is but I thought I would mention it.

It seems like Cylinder#2 is low in compression. ?

Does this indicate a bad exhaust valve?

I'm going to do a cat swap today if the weather permits.
Swap your cat and go from there as far as your lack of power issue is concerned.

1)The 10 PSI below minimum is not causing your current issue.
2)If you really want to know where the compression loss is you now have to run a Cylinder Leak Down Test.
a) A compression test shows the engines ability to build pressure, a cylinder leak down test shows the engines ability to hold pressure and where the loss of compression is coming from.
Without running a leakdown test you can only make an uneducated guess where the compression loss is happening.
b) You need a cylinder leakdown tester and an air compressor that can produce and hold a minimum of 100 PSI.
c)Remove all spark plugs.
d)Bring #1 cylinder to TDC on a compression stroke
e)Install the hose from the leakdown tester into #1 cylinder and connect to the leakdown tester.
f)Hold the throttle plate wide open, remove the radiator cap and the oil filler cap.
g)Connect your shop air to the leakdown tester and slowly open the air valve until the shop air gauge reads 100 PSI.
(You may need a helper to use a breaker bar and socket to hold the crankshaft still, the piston will want to travel to the bottom of its stroke when the air pressure is applied)
h)Read the pressure on the other gauge, that is the PSI the engine is holding in that cylinder.
i) Turn the crankshaft 90 degrees clockwise (which will bring #3 cylinder to TDC) and perform the leakdown test on the next cylinder by firing order.
Firing Order 1, 3, 4, 2 Clockwise
j)Repeat until all 4 cylinders are done.

READING YOUR RESULTS
1)Naturally you want to be as close to holding 100% in each cylinder (100 PSI) as possible
The max loss allowed on each cylinder would be 25% for rings, 10% for intake/exhaust valves, 0% for loss into the cooling system.
2) To know where the loss is coming from you need to use your eyes and ears.
a)When you are testing each cylinder listen at the throttle body, oil cap opening and exhaust pipe, and look at the coolant in the radiator.
What Each Means, Air Heard From The...
1)Throttle Body indicates a leak from the intake valve
2)Exhaust indicates a leak from the exhaust valve
3)Oil Filler Capopening indicates leakage past the rings
(Some loss past the rings is normal, you are allowed up to a 25% loss)
4)Bubbles in the coolant indicate a headgasket issue (in worse case scenarios it could also mean a cracked head or block)

CYLINDER LEAKDOWN TESTER
This is the one I own.
https://www.tooltopia.com/otc-tools-5609.aspx

HOW TO
https://mobiloil.com/en/article/car-maintenance/car-maintenance-archive/how-to-do-a-leakdown-test



 
#25 ·
I was going to swap in a universal cat today -- but the cat was too small and I wasn't about to self induce a headache trying to add sections and clamps to make it work... I also noticed the cat that was given to me (as well as other options provided from other parts stores) was missing the tie-in point that I believe recirculates the exhaust... I will attach a photo of what I am talking about.

If it is absolutely necessary that I get a cat with this connector in the middle then I have to know for sure that the direct fit Magnaflow (#23252) will have this connector? The photo they provide is just a 3D render.


Connector in question:
Auto part Pipe
 
#28 ·
The air pump/aspirator system flows air into the Co/HC portion of the cat since O2 is needed for the Catalyst to work. Since you do not have emissions testing it is your choice weather to leave the aspirator tube disconnected from the Cat. If you do save the pieces. You can measure the length of your Cat, get the inlet and outlet pipe diameter and go to the Walker Exhaust website and it will lead you to a universal Cat with those specs. I will be away until Monday if you have any issues.
 
#29 ·
VICTORY!! So to touch bases on the situation. I replaced the cat with the direct fit part above and that did it. the membrane was broken into a few pieces. it's possible some traveled into the resonator but I didn't actually check unfortunately it didn't cross my mind to do so when I was installing the new section.

Runs like a dream now. going to be putting it up in storage shortly now that the snow has began to fall.

I had to remove the aspirator because the cat didn't have a connector for it. I kept the part but completely removed it and capped the portion that connected to the manifold/engine . I was told this should be okay and won't affect performance

The next thing I'll look into doing is that leakdown test
 
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