1999 seville sls. car was running fine one day it started acting upp and died on me twice in an half an hour no codes,,,humm started up fine so went on..the car a few weeks ago was hesatating while upon acceleration. check all the fluids ok, i just did a tune up 6 months ago so spark plugs and oil and radiator fluid ok...my wife was driving the car to work when she called me and said the car sounded like the muffler fell off. I drove over to meet her and when looked in the engine the boot and plug (still connected) popped out and was lying on the manifold....ok maybe the plug was lose and the combustion shot it out.... i keep my tools with me so I brushed it up with a wire brush and put it back in.... NO CODES.. I then took the car and drove it my self. it was hesating during acceleration and you would hear a backfirein the engine....NO CODES...ok so i change the spark plugs do an oil change again put premium gas and fuel injector cleaner in. checked the air filter for cloggs, checked the gap in the plugs, reset the computers both obd2 and disconecting battery...everything fine still hesatating.....NO CODES


1. could it be a bad wire
2.clogged fuel injector of fuel filter
3.engine bad
4.egr valve or va*** issue
It would make me feel better if there was an engine light on or something but NO CODES
someone pleaseHELP BEFORE I BLOW THE ENGINE!!!!!!

 

Well, yet again I post something and then go andanswer my own question before I get a REPLY (cadillac forum makes me think)...Anyone who has this problem check your EGR valve...that is why it had a gas smell it was very easy to replace 2 bolts scrape off old gasket repleace with new one and plug in..to bad it cost $175.00 at a parts store..lucked out and paid $ 36.00 on Ebay for a new one...I LOVE EBAY YEAH....thanks anyways guys

 

Good to hear that you fixed it. It has been suggested that the EGR passages can clogg as well and then as a result heat up the spark plugs so that they do odd things like cracking or blowing out. You may want to check that those passages are clear at some point soon too. My mechanic says you need to make up some sort of reaming tool to do it and for teh most part they are accessible, just follow them to and from the EGR valve.

 

Well I changd the EGR thought it fixed it but it didnt. So I started with the cheap fixes. Pcv valve changed for $4 but no, dirty fuel filter maybe $ 8. took only 7 min to change was very dirty. but didnt fix problem. hmmmm so I went to auto zone and had them , FOR FREE, hook up the scanner what do you know miss fire in cylander 5. so i bought a ignition coil for $ 33 dollars at auto zone but inon in 5 min and now my problem is gone. So for $100 (the cost of an estimate at the dealer)I replaced allparts for a tune up and fixed the problem. so for anyone else who has this problem take it to get scanned if no codes come up on your car obd2

 

good job sneak, way to track it down, and thanks for posting the results. It's comments like yours that make a "forum". This one is just getting off the ground, hope you continue to support.

G.A.R.Y.