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86 olds 98 regency popping noise at throttle body


Meck46
02-28-2008, 12:03 AM
Hi everyone

I have a 86 olds 98 regency with a 3.8L engine, I have a popping sound coming from the throttle body, when its idling, knot so bad when I give it more gas. I change the coil pack and ignition modular, plugs, I all so pressure tested the fuel pump,all good. can anybody help.

Thanks meck46

brcidd
02-28-2008, 08:14 AM
make sure you have the plug wires on the right coil terminals-- these engines can run with 1 and 5 reversed and pop like you describe-- there is a diagram on your underhood sticker- usually on radiator support...

Meck46
02-28-2008, 11:58 AM
Thanks for the reply. The wires are on right I recheck with the decal, any other suggestions.

Thanks Meck46

brcidd
02-28-2008, 02:36 PM
Has the timing chain and cam sprocket been replaced lately?-- my '86 Park Ave-- same engine, same car as yours- skipped a few teeth a month ago- when the dampner shoe broke loose- took me awhile to understand why it ran so bad-- until it crunched 7 of 12 lifters!! interference engine you know....anyway- I had to pull the front cover off- the cam sprocket was nearly worn off- all the teeth were about gone-- and I had replaced the timing chain and sprocket 50,000 miles ago-- but I failed to replace the dampner-- and it broke this time...

The original cam sprockets are known for wearing the nylon off and pieces getting sucked up into the oil pump screen.....was yours ever done???

Meck46
02-28-2008, 07:21 PM
I talked to the last owner and he hasn't changed the timing chain or sprockets, so that could posible be it, I'll pull the timing cover off and check it. Thanks for the sugestion I'll let you know.

thanks Meck46

Meck46
03-02-2008, 12:14 AM
Well I changed the timing chain and gears and it still popping from the throttle body. There are no codes stored. Will plug wire do this even if I have spark to all plugs or what about a worn cam.

brcidd
03-02-2008, 08:49 AM
Only thing I can think off is a sticking valve-- have you ran it with the valve vovers off? to watch the valves??

auto trainy
03-02-2008, 10:33 AM
A worn cam would do that,if one exaust lobe is worn it would not allow the exaust gas to be expelled completely and when the intake valve opened it would pop like you are getting ( not definate but a posibility ) the only way is like stated is to remove the valve covers and observe the rockers. Good Luck

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