Not a TDI at all but I need your advice

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Greetings everyone.

Yeah, I know this is not a TDI-related and it's not even a diesel.. But guys, I need your advice as you're the best..

My mom has got a Vauxhall Corsa D, 1.4 liter gasoline engine (engine code Z14XEP, 4 cylinder engine, if that matters).
The car is 9 years old and has got 70k miles on the clock. She doesn't drive a lot.

Unfortunately, about 1000 miles ago the car developed a connecting rod knock, at least it looks to me so. At first it was clearly heard on cold engine, let's say upon first start in the morning. Once it warmed up a bit the noise is gone till the next cold start.

Now 1000 miles later it knocks bad on both, cold and hot.

I understand that it's time to have the wrenches turned. However, due to family problems the car can't be serviced during upcomming week; it will need to wait at least one more week...

Question: how safe is it to drive with connecting rod knock? Can further damage be done? Or should the car be parked till it gets service?

Also, any ideas on how to properly nail down it to particular cylinder?

For those interested, the car has been serviced at regular intervals, oil and filter always changed by me at 7k-9k mile intervals, always used proper oil and a quality filter. Honestly, I have no idea why such a problem occured at that low mileage...
 

HPsenicka

Veteran Member
Joined
Aug 15, 2013
Location
Orangeville, Ontario
TDI
2 x 2004 Jetta Sport BEW (Malone Stage 1.5), 2014 GSW TDI - Wolfsburg Edition, 2015 Passat TDI -Sport Trim
If it is truly a connecting rod bearing that is causing the knock, it will also be wearing on the crankshaft creating more damage.

Best not to drive it further until the the problem is definitively diagnosed, which will likely require dropping the oil pan for closer inspection.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Thanks for chiming in.

I really hope that this is a bad rod bearing as such issue is probably easiest/cheapest to fix. I really don't want to pull the head off or even replace entire engine..

An idea came to my head. What if I remove the spark plugs, turn each cylinder to TDC and then until it slightly starts to move down. Afterwars use a long metal stick or a screwdriver and try to put some force on the piston. Assuming the crankshaft is locked (an assistant holding the breaker bar), if there's some play, the piston should slightly move down.
Question: is this realistic? How much of play can I expect? I know that the movement will be a hair or even less but just wondering if it's worth to try before some time can be devoted for dropping the oil pan and pulling the bearings....
 

Mike_04GolfTDI

Top Post Dawg
Joined
Nov 19, 2003
Location
Richmond, BC, Canada
TDI
Mine: 2019 Golf R DSG, Wife's: 2015 Golf Comfortline TDI
A compression test might be an easy way to identify which cylinder has a problem.

A compression tester for a gasoline engine is not expensive. (They're a little more for a diesel engine.)

I would think the cylinder with the bad bearing would give a lower reading, because the piston isn't moving quite as far.
 
Last edited:

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
Here is the method I have always used to check a gasoline engine for rod knock: with the engine idling, pull the spark plug wires off one at a time; if it is rod knock when you find the cylinder with the problem the knocking will usually diminish or even go silent.
Is it possible you have a crashed tappet? If after testing the individual cylinders don't make it obvious you have actually have rod knock, you may not have rod knock. At 70k miles and bad tappet is much more common that a rod bearing. I hope this is of some help to you.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
We get a turbo version of that engine here. They are a throwaway turd. Short lived, very light duty. I would have thought yours being (I assume) non turbo it would have lasted longer.

The TSBs GM has on those here could fill a book. Ranging from the crankcase breather/valve cover problems to bad block bores to lifter failure to noises from poor quality oil filters. Nice to know GM is no better over there than they are here.

You may look into carbon build up on the intake valves though. That can get bad enough to cause a noise, and is usually joined with a misfire DTC, and can sound pretty bad.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Here is the method I have always used to check a gasoline engine for rod knock: with the engine idling, pull the spark plug wires off one at a time; if it is rod knock when you find the cylinder with the problem the knocking will usually diminish or even go silent.
Is it possible you have a crashed tappet? If after testing the individual cylinders don't make it obvious you have actually have rod knock, you may not have rod knock. At 70k miles and bad tappet is much more common that a rod bearing. I hope this is of some help to you.
Yeah, I know that but... It's not a single coil per spark plug, it's entire coil pack assembly:


So unfortunately I can't do that test :(

I have listened very carefully in various areas. It definitely doesn't sound like a bad tappet at all. It sounds like a rod knock for sure, 1st or 2nd cylinder most likely. The sound seems to come from bottom end.

I'm really surprised to see a rod knock at 70k miles too. Hard to believe such things happen but I'm facing one right now...
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
We get a turbo version of that engine here. They are a throwaway turd. Short lived, very light duty. I would have thought yours being (I assume) non turbo it would have lasted longer.

The TSBs GM has on those here could fill a book. Ranging from the crankcase breather/valve cover problems to bad block bores to lifter failure to noises from poor quality oil filters. Nice to know GM is no better over there than they are here.

You may look into carbon build up on the intake valves though. That can get bad enough to cause a noise, and is usually joined with a misfire DTC, and can sound pretty bad.
Yep, mine is a non-turbo version. Although in later model years it was offered w/turbo here too.

I visited a few salvage yards around here; called a few more. None of them have such an engine for sale. One guy told me that they are so popular that at least 3-5 people per day ask about these.. The demand is quite high.

To me that engine doesn't look fragile by design. It's not super powerful, it hasn't got obvious design flaws... Hey, I even liked the design of oil pump - it's single part mechanism, no chain, no sprocket, no anything! But the reality is that these seem to be dyng like flies. :confused: Asked the same guy at salvage yards what was the problem with those engines. The reply was "everything". Cylinder heads, chains, bottom end :confused::confused:


Thanks for the tip on carboned up valves. If I have an opportunity, I will definitely check for buildup and try to do something if I will be able to. I have noticed that some time ago it was harder to start and it idled rough sometimes. Replaced the spark plugs, cleaned the throttle body (also did the adaptation afterwards) but the problem did not go away. Since it wasn't a real issue, I did not dig it further
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
Yeah, I know that but... It's not a single coil per spark plug, it's entire coil pack assembly:

So unfortunately I can't do that test :(
I have listened very carefully in various areas. It definitely doesn't sound like a bad tappet at all. It sounds like a rod knock for sure, 1st or 2nd cylinder most likely. The sound seems to come from bottom end.
I'm really surprised to see a rod knock at 70k miles too. Hard to believe such things happen but I'm facing one right now...
Yes you *can* do that test.

Get a few feet of vacuum tubing and run equal lengths from each coil to each plug. The carbon in the tubing (black colour) will conduct the spark just fine. You can then pull each plug "wire" in turn to short each cylinder.

Use insulated pliers and good thick rubber soles... unless you like 40kv shocks. :D
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Yep, mine is a non-turbo version. Although in later model years it was offered w/turbo here too.
I visited a few salvage yards around here; called a few more. None of them have such an engine for sale. One guy told me that they are so popular that at least 3-5 people per day ask about these.. The demand is quite high.
To me that engine doesn't look fragile by design. It's not super powerful, it hasn't got obvious design flaws... Hey, I even liked the design of oil pump - it's single part mechanism, no chain, no sprocket, no anything! But the reality is that these seem to be dyng like flies. :confused: Asked the same guy at salvage yards what was the problem with those engines. The reply was "everything". Cylinder heads, chains, bottom end :confused::confused:
Thanks for the tip on carboned up valves. If I have an opportunity, I will definitely check for buildup and try to do something if I will be able to. I have noticed that some time ago it was harder to start and it idled rough sometimes. Replaced the spark plugs, cleaned the throttle body (also did the adaptation afterwards) but the problem did not go away. Since it wasn't a real issue, I did not dig it further

Yep, they are a real loser of an engine. I am sure that is why your salvage yard fellow gets asked about them so much. We see a few with blown chains and rods out the side of the block occasionally too. More times that not, the car is not fixed. They are low dollar (in the used market) cars here, so there is little chance anyone spends the money to fix one.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Yes you *can* do that test.
Get a few feet of vacuum tubing and run equal lengths from each coil to each plug. The carbon in the tubing (black colour) will conduct the spark just fine. You can then pull each plug "wire" in turn to short each cylinder.
Use insulated pliers and good thick rubber soles... unless you like 40kv shocks. :D

Pretty interesing idea! Didn't know that... Probably need to try that.

Yep, they are a real loser of an engine. I am sure that is why your salvage yard fellow gets asked about them so much. We see a few with blown chains and rods out the side of the block occasionally too. More times that not, the car is not fixed. They are low dollar (in the used market) cars here, so there is little chance anyone spends the money to fix one.

Do you have Opel/Vauxhaul brand there?
Never heard of Cruze, Sonic, Encore at all...


Back to the matter.
Today the workshop had an opportunity to take a look at the car. They drained the oil to a clean container and dropped the sump. No metal shavings there, no anything. Magnetic drain plug is clean with some "graphite-like" stuff on the tip, nothing unusual.

They pulled the rod caps. Rod bearings (shells) look like new on all cylinders. No scratches, scoring, wear - they look absolutely brand new. Two mechanics checked for piston pin play and none of them could feel any. They tried to move the crankshaft side to side too - no movement.

At this point everyone was puzzled. They put everything back together and had no further ideas. Tomorrow the car wwill be visiting another shop for a second opinion.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Opel has not sold a car here in 40+ years, but it is all corporate GM anyway so we do get some Opel models just rebadged. The Astra was sold here under the ill fated Saturn name towards the very end. Catera, GTO, LeMans, Chevette, Solstice, Sky, and others were all Opel models that were rebadged/modified for US sales.
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
At this stage, you need the ear of an experienced mechanic who has heard all these noises first hand.

Bad rods, mains, piston slap, worn wrist pins, bad lifters/rockers/cams all make similar but different noises.

You need someone who has heard them all to listen to your engine.

A stethoscope helps too - one made for the purpose. It would help to isolate where the noise is coming from (top or bottom of the engine, which cylinder etc.)
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
Opel has not sold a car here in 40+ years, but it is all corporate GM anyway so we do get some Opel models just rebadged. The Astra was sold here under the ill fated Saturn name towards the very end. Catera, GTO, LeMans, Chevette, Solstice, Sky, and others were all Opel models that were rebadged/modified for US sales.
I miss my Chevette - that car was bulletproof. Always started on the coldest of days.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
At this stage, you need the ear of an experienced mechanic who has heard all these noises first hand.

Bad rods, mains, piston slap, worn wrist pins, bad lifters/rockers/cams all make similar but different noises.

You need someone who has heard them all to listen to your engine.

A stethoscope helps too - one made for the purpose. It would help to isolate where the noise is coming from (top or bottom of the engine, which cylinder etc.)
Well, the shop which the car was today in had a mechanic with decent experience.
He told that it's not cam, lifters or chain tensioner for sure - the sound seems to come from bottom of the engine. He suspects cylinder #1.

Tomorrow I will get a second opinion on this. I received a call just an hour ago and they told me that a mechanic from official Opel/Vauxhall (you name it) dealership will visit the shop to help diagnose the problem. He's supposed to be the one who works with engines in-warranty and post-warranty period.

I really pray this issue to be finally nailed :(
 

Mike_04GolfTDI

Top Post Dawg
Joined
Nov 19, 2003
Location
Richmond, BC, Canada
TDI
Mine: 2019 Golf R DSG, Wife's: 2015 Golf Comfortline TDI
I once rebuilt a Toyota Tercel engine that had a terrible bottom-end knock.

You couldn't see anything wrong just by looking, but by measuring the connecting rod bearing journals on the crankshaft the bad one was slightly oval.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
I miss my Chevette - that car was bulletproof. Always started on the coldest of days.

Mine was a complete pile of crap, same as every other one I have ever laid hands on, including the one my aunt bought brand new. Of course, mine always started and ran perfect, even as I drove its junky falling apart carcass to the scrap heap. The Isuzu diesel engine was by far the best part of that poor thing. Good news is, as parts fell off, it went faster and used less fuel! But when the rear spring perch broke off, it was done. Amazingly that engine pushed that junker over 300k miles, and the engine was still fine.
 

Windex

Top Post Dawg
Joined
Apr 1, 2006
Location
Cambridge
TDI
05 B5V 01E FRF
Mine had the (west) German gas engine. Gutless but never gave me grief. Sold mine before it could become a rot box.

Never saw one of the diesel variety in the flesh - only heard about them.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
As promised, some update today.
The mechanics who were looking at the issue at the second shop today decided it was hydraulic lifter(s) faulty causing the knock. Personally I am in doubts as to me the frequency of the knock looks corelated co crankshaft speed but not camshaft but anyway..

So they pulled the chain, cams, rockers and took the lifters out. Obviously, nothing visually wrong was seen. New set of lifters has been ordered, INA brand.

Will it solve the problem - I don't know. But the fact I know that the game "let's throw some money into it" has definitely begun :)
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Well, a full set of lifters and a week later, it sounds the same :(

The knock is there, the same as it was before. No idea what to do next... :(
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Well, a full set of lifters and a week later, it sounds the same :(

The knock is there, the same as it was before. No idea what to do next... :(
Replace the engine. Or replace the car. Truthfully with all the great choices in small cars you have there, I would tend to go for the latter.
 
Top