75 99 ems running rough

[donaldderby]

Ok guys just picked up a 75 99 ems she starts fine but runs really rough when driving, mainly just sputtering no backfireing but over all isnt right. Im new to older saabs but was told this can be indicitive of a failing headgasket but i did a compression test and cooling test and everything was good. so my question is this, does anyone have any ideas aside from the plugs cap and wires which are all brand new. Thanks in advance.

[rev_pat]

You didn't say how many miles on the motor, however, you might have an air leak of some kind. Check all gaskets and hoses first. It might seem like a basic answer, but on my 99 I didn't have a gasket between my cold start valve and housing and that cause idling problems. Next, I would check the timing. The basic stuff as you mentioned, plugs, wires,rotor & distributer, start there. You'll get it.

[donaldderby]

sorry should have mentioned body has 237k on it the motor supposedly less but the po doesn't know how much less, to me the motor looks to have the same "patina" as the rest of the car so i have my doubts . Thanks for the tip i figured it was vacuum related but other that vw diesels i have little experience with mfi. That reminds me though, is there any specialty tools i should start looking for now? Thanks again.

[rev_pat]

Probably the best tools would the factory shop manual which you can purchase off of Ebay. The Saab 99 Owner's Workshop Manual Haynes would help too. The factory shop manual has a list of all the tools that you would need. However, specialty tools are hard to find. One must have are the microfiches for the car in.pdf file format. They show just about every part with associated Saab part number. You can zoom in and see the part up close and how things go together. Standard Metric tools, test light and ohm meter are a must too.

[nutcase]

Agreed, a decent Saab produced manual is a must. I'd suggest keeping an eye out for a waterpump extraction tool (I *think* a 75 will need more than a slide hammer - DO NOT USE A SLIDE HAMMER if it says not to as you'll smash the cogs). Shouldn't be a rush to get the pump tool but it's nigh on impossible to safely do the waterpump without it. Other than that, maybe keep an eye out for the fuel pump removal tool, but again not urgent.

I can help with the fiches but would have to charge a little bit I'm afraid as it cost me a small fortune several years back to get it all scanned.

[donaldderby]

id definatly be interested in scans pm me the cost. Thanks again all

[donaldderby]

i did notice what looks like a vacuum advance unit or egr diaphragm underneath the intake from what i have gathered it is some type of fuel regulator. Their is no vacuum line hooked up to it. Where should it be connected to. I would take a picture but i wont have the old girl here until Friday.

[donaldderby]

i think i found the source of my problem where should this be hooked up to