1998 GLT Hiccups on Freeway or at a stop light very intemittent - NO CODES or CEL
 

Need your help guys. My 1998 S70 GLT hiccups on the freeway and at stoplights very intermittently. At lights maybe once or twice a day and on the freeway once every 30 miles or so.

Any ideas?

It has 140k, I have replaced the plugs (bosch Plat), wires (OEM), cap (Bosch), rotor (Bosch), air filter (autozone), timing belt (IPD Kit), cleaned the throttle body using throttle body cleaner not carb cleaner.

Thanks.
Maybe TECH will chime in and nail it like he always does!

Bump?

MAF Dirty? Nothing?

Did you gap your spark plugs? You can try to gap them to right spec to see if it will make diff.

Try cleaning the MAF... also, These cars can be kind of picky about plugs, and Bosch Platinum wouldn't be my choice. If you didn't gap them, do so, or replace with OEM plugs, or even Denso TT plugs. Both work great in these engines.

I re-gapped them to spec when i installed them (even called IPD to make sure I had the correct spec as I knew plugs were an issue if not gapped correctly). I have even had to change out a friends back to his old ones (dug out of the trash) cause his car wouldn't start after he replaced with Autolite platinum.

I cleaned the MAF recently, but haven't driven it yet myself (just the wife).

Thanks for the tips.

Wait, you said this is very intermittent, right? If the ignition had a system fault it usually isn't intermittent (though it may only show up under heavy load).

And what exactly do you mean by "hiccup"? Do you mean a misfire like one or more cylinders are dropping out, or does the engine smoothly loose power for some number of seconds?

If it's more the latter, I would look at fuel pressure issues; possibly fuel pressure regulator or more likely a faulty fuel pump relay (known for its intermittent behavior when they start to fail).

Are you sure your CEL is working? I can't believe this isn't setting any codes. Let us know what you find.

Hiccups
 

I am having the same problem. I let mine idle in my driveway and it eventually threw a code p0410. Its air pump or valve. Car runs normal after warm up but hiccups or eratic power loss on freeway and traffic lights

My 1998 V70 w/ 100K miles had the exact same symptoms.
Then threw code P0103 (Air Mass).
Installed new BOSCH (and yes use only BOSCH!!!) Air Mass (bought on ebay from "germanautosupply" for $145 incl. shipping) and all is good!