Hello, I had recently purchased a 2003 golf gti AUTOMATIC (with optional shifter) with a 1.8 turbo 4 cylinder engine. The vehicle has 139,000 miles on it. Before purchasing, I had a mechanic come out and look at the vehicle for a pre-purchase inspection, and ran the code P0303 (cylinder 3 misfire) which without test driving, told me that is what caused the shift shudder I noticed when I had test driven it a previous day. He told me the coil packs were in good condition by looking at the top of them, and told me if I replace the spark plugs, the issue should go away. I feel it is important to mention that he had also run codes on the transmission and nothing came up. Taking it home, this morning I had replaced the spark plugs and driven it for about an hour both regularly and aggressively to test it. The problem is still there, and I was really hoping that there is a solution to this problem, because everything else on the car is beautiful, while being my dream car, I just want it to work as well as I know it can. To be more descriptive, when shifting to 3rd the whole car feels basically like it is tripping over itself before successfully shifting. I appreciate any help offered in resolving this issue, thank you very much! -Christian H.
Well… I own the same vehicle… albeit the 20th Anniversary GTi 6sp manual model…but everything under the hood is essentially the same. Your “Mechanic” who looked at the tops of your coil over plug system must be a Magician because you cannot tell the condition of the coils by looking at them.
This vehicle was involved in a Coil Recall… Look it up… VW will replace all the affected Bosch COP units with the new and updated part. Perhaps the guy was looking at your part numbers to see if they were already done ? I dunno… Even if they were done…this doesn’t preclude them from normal failure.
Look into the recall…see which units you have… Replace as needed… If you have a failing coil…its not going to go away till you replace the unit. Once you do…it will be smooth sailing… You cannot look for a smooth running engine or smooth trans till all coils are working. This is a common failure. It is also extremely ez to remedy… if you can change a light bulb…you can change a coil pack. One 10mm nut and your fingers do the job nicely. It takes seconds to do. That is IF you dont need all of them done under warranty. If you do…then VW needs to have the car for an hour or so…they wont just give you the packs to do yourself since its a recall.
They also recalled the brake light switch…again they need to install it… Something about the new “green” colored switch is what they use now… The original goes bad and applies the brake lights constantly…
The misfire could indeed be the cause of your symptom. There’s no way to tell except by figuring out what’s causing the misfire and eliminating it. It pretty much has to be from among a faulty spark, fuel, or compression. Spark is the easier of the three to eliminate, that’s likely why your shop said to replace the spark plugs. It could still the be coils, the ignition module, or the cam or crank sensors. That’s probably where to look next. If I had this problem I’d be looking for a shop with a VW specific scan tool with real time diagnosis capability (i.e. mode 6) and a lab o’scope. That’s the quickest way to get to the bottom of it.
Begin at the coils…they are known failure culprits… Also help to have the VAG-Com interface…basically a dealer level OBD2 diagnostic …tells you everything you could possibly want to know.
Look your VIN up and see if it has had the recalled parts replaced…many have not. Mine didn’t…
Thank you guys very much for the replies, so i replaced the plugs and the P0303 code went away but it is still making the hard shift to 3 and 4 so im assuming it isnt a stem from that code
Ok, it’s great you’ve eliminated that misfire code as the source of the shudder. Next up, I’d test for a possible torque converter shudder problem. The TC is supposed to lock-up in certain speeds and power demands, which is done to increase the car’s mpg ratings. i.e. when it reaches that speed, it acts just like a manual transmission with no mpg-robbing slipping motion occurring in the TC. Sometimes the transmission gets confused and can’t decide whether it should lock up or not, and the indecision of lock then no-lock then lock etc makes the whole car shudder, usually this is reported to occur around 30-35 mph. On some transmissions the lock-up mode can be temporarily disabled, and if yours is one of that type, that’s a good way to prove whether the lock-up mode is the cause.
Here is where a laptop and the VAG-COM software pay for themselves instantly…
Okay! Ill look into it and post an update when im able to complete that task tgis weekend, also being a newbie i dont really know about vagcom or what it is
Thats why we have the internet…
I know, I’m reading into it
I’m not real sold on a mechanic who can eyeball a coil terminal and pronounce the coil good.
Just some food for thought here. The mechanic said plugs should fix the misfire. The plugs were replaced and the misfire is gone.
Now what happens if the misfire returns due to oil consumption, low compression, or what have you?
I sincerely hope the plug failed simply due to high miles.
Just my 2 cents, but as a mechanic I’ve done a lot of vehicle inspections both for dealers and individuals. I would have advised you to back away from this car unless the problems were resolved pre-purchase or Option Two; a lowered price with your full understanding that you may be wading into something that could be a headache; or multiple headaches.
I’m not knocking VW GTIs. On the contrary, I love them.