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help..engine surging

943 Views 7 Replies 5 Participants Last post by  Spitzenklasse
my '97 E420's engine surges at idle. the needle on the tac is bouncing like someone's foot is taping on the gas pedal. but whats odd is that im not getting any warning lights. i had the same problem but with warning lights in January caused by a bad MAF sensor. i replaced it and all has bin fine till now. can anyone help me out??
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my '97 E420's engine surges at idle. the needle on the tac is bouncing like someone's foot is taping on the gas pedal. but whats odd is that im not getting any warning lights. i had the same problem but with warning lights in January caused by a bad MAF sensor. i replaced it and all has bin fine till now. can anyone help me out??
Did you get a genuine MAF? This is what all recommend.
Wow. You joined in December '06 and this is your first post? WOW!

Please click the User CP link and complete your profile for the forum to including your vehicle and location (heavily suggested by your username, but helpful nonetheless).

Warning lights are not the only issue (aside from the point that bulbs can burn out). Get a code reader and scan for codes. Codes can store in the absence of a CEL and can point the way to the problem.

Assuming you've regularly changed your gas filter, air filter, spark plugs and other routine items this could be caused by bad connectors on the coil side of the wires, as well as one or more dirty injectors, etc.

But start with codes and go on from there.

Take care and enjoy the ride,
Greg
i changed my coil 8 months ago...

air filter is good..plugs are good..fuel filter could use a change. Is it a big job to get to it? is it something that i could do my self? I noticed my vacuum hose looks wore out and probably needs replacing. Could that be causing it? Id love to run a diag to find the error codes but nobody will do it for free..the cheapest i could find was $60 bucks. so i would rather just buy my own scanner but im not sure if my car is an obd2 or not. the connection under my dash is a square 16 pin plug. Does that mean its an obd2. Can anyone recommend a good scanner? thanx for the help fellas.....:thumbsup:
Vacuum hoses should be inspected any time you have unusual running issues. So sure take a look. Used carefully and with proper ventilation propane is useful for helping to locate them.

All cars marketed to the US beginning with MY 1996 comply with OBD-II standards. Any OBD-II meter will read codes, you don't need one to translate for you, just alphanumeric codes is fine. Read and erase is all you need.

You've been around a while but just started posting, may I suggest that you spend a little time reading through the titles of the DIY/Help stickies? There is a wealth of information in there, including some information about code readers and an excellent DIY for changing the fuel filter. You can indeed DIY that and autohausaz.com often has the Bosch fuel filters on sale.

Take care and enjoy the ride,
Greg
Sorry for the late responce...

Ok, i bought a scanner hooked it up and got one pending error code. The error code is P0410. I dont know where to go from here. hopfuly one of you can help me out..:confused:
thanks for all the help sofar greg:bowdown: its much appreciated.:thumbsup:
PO410 Air Injection system malfunction
A vacuum leak will cause the idle to be too high and make the engine surge. I've had a loose vacuum hose fall off once or twice and that is what happens. Reconnect and everything is fine.

Lift the hood with the engine running and listen for air leaks (if a hose is off it's easy to hear).
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