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99 2.0..dies off idle

5K views 23 replies 6 participants last post by  tedybear 
#1 ·
Not my car but I have the "pleasure" of working on it. I let a female friend drive my car until I can get her bug going again and I REALLY want my car back!:)
The car starts fine and idles fine, if you give it any gas it just dies as if you turned the key off. Let off the gas and it will come back to idle. I thought it may be fuel related and did a pressure check. The Bentley manual says 36 psi at idle, 44 psi with regulator hose disconnected. This bug runs 44 psi with or without the vacuum hose unplugged so maybe the regulator IS bad but would it explain the conditions I've described? My thought then turned to maybe a plugged cat but not sure it would explain this condition either.
I did ask her if this was sudden or gradually occurred and she said it had seemed to be down on power lately but she could still drive it...until now. She also told me it seemed to get better the longer the trip...until now.
She bought this thing used and over the past couple years anything I have done to it there was evidence someone else had been there before due to broken tabs, incorrect clamps, etc. Any suggestions would be greatly appreciated as I'm not real sure how I'm going to get my Element back if I can't give her the bug back! Not a good situation I've allowed myself to be in but she's definitely on a budget.
 
#3 ·
No cel. Having never experienced a clogged cat I wasn't certain what the symptoms would be other then lack of power. I had planned to drive this thing a short trip to see how it behaved, went about a 1/2 block and literally put it in reverse to get it back to my garage, that's how bad it is!
 
#4 ·
I doubt the fuel pressure regulator is the problem. If it is not working the result is a slightly less smooth idle. You could just have a cracked hose. The original one is very prone to cracking and causing a vacuum leak.

I agree about testing the cat by removing the front O2 sensor. It is not the easiest to get at on the AEG engine, but definitely worth a try.
 
#5 ·
I like the idea of removing the front o2 sensor as well. First I have a infrared temperature gun I'm going to shoot the temp in front of the cat and behind the cat to see if it tells me anything. Odd as it sounds I almost hope it is the cat as if it's not I'm not sure where to go from there! I do remember her telling me the exhaust has been rattling and I thought at the time probably heat shield but now I'm wondering if it was the first sign of doom. :)
 
#6 ·
I know you checked the fuel pressure. Was it at idle or were you able to check it while driving the car. A clogged fuel filter can still have the right pressure and not be able to keep up with the necessary flow. Also how old are the plugs and wires. I once had an Accord that as the plugs wore down it lost the ability to rev up to the point that it wouldn't go over 2000 rpm.
 
#7 ·
Good point on the fuel pressure vs volume. I intend to check the fuel volume delivery per the manual as well but didn't have a shut off on my pressure gauge and a graduated beaker to measure delivery.
Fuel pressure was checked only at idle and the plugs and wires are not new but recent.
 
#8 ·
Definitely NOT the cat. The cat rattled and checking with an ir gun determined it wasn't doing anything anyway so I gutted it.
Car seems to run fairly clean and peppy to 2,000 then falls flat. Increasing the rpm slowly in park it increased fine to 3,500 rpm (as far as I tried) but if you hit the throttle quickly it replies with a blah. I tried driving it and up to 2,000 rpm it accelerates smoothly and even with pep but then falls flat after 2,000. From a rolling start I hit the throttle briskly and again it just dies as if you turned off the engine. Occasionally it did sputter above 2,000 but for the most part just blaaah.
 
#9 ·
Haven't gotten it solved yet. Hope it will limp in to get the codes read. I pulled the fuel pump kind of expecting to see the screen at the bottom plugged but instead it was spotless. Forgot to mention I've also replaced the fuel filter. The fuel dumped from the filter was absolutely black but it made no difference in it's running. Still runs fairly well up to 2,000 rpm then falls flat. For the heck of it while parked I pushed the pedal to the floor and held it, the most it could muster was a sick sounding 1,500 rpm.
 
#10 ·
About to throw in the towel though I hate giving up. I want my Element back! Now she tells me the cel came on in the Element. I think she's jinxed. I'm going to clean the maf sensor, possibly still check fuel volume though I've checked fuel pressure, then help her get it to a shop. Unless of course someone chimes in with more advice!
 
#12 ·
She has never seen the cel on and it's not on while in my possession either. She did tell me today the Element I let her borrow has a check engine light on now! I've put 30,000 miles on the Element and never a cel. I can't get a break! :dunno:
This poor bug had obviously led a rough life from the previous owner. It kind of has a laundry list of things that need attention (poor heat, new grill, etc.) but it seemed to always run decent until recently.
I've been thinking about getting a code reader and trying to educate myself on it's use and now may be the time. I've read much of what member jfoj has posted regarding them but I'm still kind of in the dark.
 
#13 ·
I would urge the use of VCDS-Lite and the interface cable that you can nip up on eBay. Yeah it's restricted until you shell out the $$ to purchase the copy of it. (and it requires a laptop..or a realllllllllllll long USB cord) The smart phone app with the blue tooth adapter is also worth checking out. (I have a rather dumb phone, so that wouldn't work out)

Thing is, just because the CEL isn't on? Does not mean the computer didn't store any codes that may be useful. Our CEL with our 2.0 was 'off' but had 6 codes stored in memory.

In fact what you've described sounds more like a blown coil pack. However that should be tossing CEL's like there's no tomorrow (eg: blown coil pack shorting out or mis-firing will occur most often when the engine is under load. electricity is lazy and will always take the path of least resistance--So when at idle the car may appear to be fine--doesn't take a whole lot to fire an unloaded engine. Put it under load? The voltage it takes to fire the spark plug increases, and the 'spark' follows the lazy path to discharge.)

However like I said? With no CEL pointing towards a P0300 to P0304 set of codes? Probably not likely.

Just a suggestion:

Pick up or borrow a scan tool that can show live data and record the data stream. Have it record and drive the car and recreate the problem. Once there? Then we can start looking over the data and see if anything pops up. Plus the scan tool can report back on any codes present. Sense you gutted the converter? I'm expecting a P0420 code to pop up.

S-
 
#14 ·
Thanks for the reply, and it will have to be a stand alone scanner. I don't have laptop and my phone isn't too bright either. :) I had thought it might have some stored codes but asked if one of the parts stores could read codes and they told me not if there wasn't a current cel. There again, yet another reason to own my own scanner but educate myself in it's use.
 
#15 ·
I was thinking...Possible exhaust restriction? Just a shot in the dark.

The converter was 'gutted', but what about maybe a bad baffle in the resonator or muffler? There's an excellent video on youtube on using a vacuum gauge to diagnose restrictions. (Look for Eric the Car Guy. He does great instructional videos. Plus it's pretty much universal for all cars for the basic stuff)

If at idle...does it have pretty decent exhaust flow out the tailpipe?

Keep an eye on Craigslist for possible decent scan tools. Sometimes you can get lucky when techs and shops upgrade their goodies :) (check eBay for a reality check however---or Amazon. Don't want to get suckered in)

(And Merry Christmas!)
 
#17 ·
Thanks guys and Merry Christmas to you all! While I had my "trap door" cut in the bottom of the converter I started it up and no change so I'd rule out exhaust restriction. I'm 58 years old and have always fixed my own vehicles. I've not once taken a vehicle in so you could say I'm slow to give up! Part of it is the satisfaction, the other part is the opportunity to learn and it's probably overdue to learn more about ODB2. Forgot to mention the crank position sensor has been replaced maybe 6 months ago when it had a no start condition.
 
#18 · (Edited)
I've been watching this post since I posted. Have you changed the fuel filter? Try to go out tonight with a spray bottle of water and mist around the coil, spark plugs and wires and see if you have a light show. If so, you need to do a complete tune up. Be sure to use dielectric silicone on both ends of your plug wires to seal out moisture. Also what shape is your air filter in and is there any vacuum leaks around the throttle body?
 
#19 ·
Forgot to mention I've also replaced the fuel filter. The fuel dumped from the filter was absolutely black but it made no difference in it's running.
We covered that.

I was leaning towards the coil pack before. However a misfire bad enough to cause the engine to run that bad? Should have set a screaming flashing CEL. (The one that is just 'on' means get to a shop soon. The flashing CEL? Means to stop driving asap and get the car checked out, before more expensive damage happens.

Severe vacuum leaks could cause a lot of headaches. The only way to see what's been going on would be to use a scan tool and check the fuel trim (long term) and see if the car has been running 'rich' trying to compensate for the extra air from the leak.

I must confess this one has me stumped. Best bet might be to see what the tool reveals.

S-
 
#22 · (Edited)
I agree on long distance troubleshooting. Anyone have a recommendation for a stand alone scanner that is VW compatible and doesn't break the bank? I stopped by two places tonight but the ones I looked at made no mention of VW compatibility. Obviously I'd like to be able to use it on other vehicles too but maybe that's too much to ask for!
Is the port that you plug a scanner in to generic, meaning all scanners fit all vehicles or are they manufacture specific? I understand by law they have to scan certain parameters regardless of vehicle manufacture while some of the unregulated functions can only be accessed by a vag scanner. I'm curious if all scanners can plug in to the bug and give me the basic diagnostics.
 
#23 ·
The bug is fixed. Turns out it was the fuel pressure regulator as I originally suspected. I just didn't want to start throwing parts at it.
After reading how the pressure regulator works and the role of engine vacuum to it all the symptoms made sense.
Oh well, the cat that was gutted was no longer performing so nothing lost there!
 
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