Hey guys!

Well, after many new parts and getting the car running well for a couple months, I've encountered a problem.

Recently it has developed a bogging [best description I can think of] issue. It does it intermittently but it started doing in once when pulling out after sitting in traffic a while due to construction. Now its doing it more frequently and occassionaly its really problematic.

It does it most anytime, after start up, after driving flawlessly for a while at interstate speed, during interstate speed or just whenever. Sometimes it will hesitate like its going to happen then it runs fine, other times it requires shutting it off and re-starting [yes, sometimes while coasting at speed] then it usually goes fine again. Sometimes it requires multiple re-starts within a minute.

I've replaced almost everything [within the last 60 days] while getting this car running well, 2 new fuel pumps, new fuel filter, new tank sending unit, new FP relay, new radio supression relay, new injectors, new distributor, cap and rotor, plugs, wires, cleaned tank, a couple fuel lines, etc...

I did clean the MAF properly a few days ago but no effect.

I'm thinking fuel related like a questionable fuel pump or fuel pressure regulator or maybe something electrical.

Weird that it usually corrects instelf by restarting it but its getting old doing this and of course I want to repair the issue.

Any thoughts?

Thanks!

 

Fuel Pressure Regulator?

 

Thanks. As mentioned above, I was thinking it was a possibility. I'm just not sure though if a FPR would act up intermittantly. It's got me baffled.

 

yeah, they can get intermittent. another cause of intermittent problems in hot conditions is the FI temp sensor on the head, or the crank position sensor, they can fail intermittently when hot, and cause bad or no running.

have you been down the 7xx FAQ troubleshooting section?
Engine Tune and Performance

 

New FPR and it's the same...........

 

After looking around a little more I noticed the ignition amplifier is damaged because the battery moved against it [oops, forgot to tighten it down] and it's broken right above the connector. I googled it and it seems this may give me the same symptoms as I'm having. A replacement is on its way...............

 

Coolant temp sensor won't cause anything but bad economy and hard cold starts. Stop throwing parts at it and do some diagnostics.

 

Good idea but there's no one locally that is worth a damn as far as diagnostics on newer stuff much less an old Volvo. I've found 2 issues that need replaced anyway and would cause these type symptoms so we'll see. I can replace several parts, maybe more for what the locals want to charge for a diagnostic that they are only guessing on.

These forums are far better than many shops, IMO.

 

No, YOU learn how to diagnose it. Like everyone else here has done. Like I said, stop throwing parts at it, work out the problems and diagnose.

 

Oh. I've never tried and as far as I know, my '89 turbo has no self diagnostic port like others have so without diagnostic equipment its still cheaper to by parts I'd imagine and at least I'll have all new parts in the end. I've had pretty good luck thus far with parts replacement which were needed regardless due to it sitting so long and I'm 99.9% confident the current issue is due to the cracked ignition amplifier. I undertstand your point though but with very limited diagnostic experience and no diagnostic equipment, replacing parts is my way. At least I'm not paying for diagnostics and parts at a repair shop that's jst guessing after diagnostics. Thanks!

 

did you carefully go down this list of things to test and evaluate ?

Engine Tune and Performance

 

Forgot to update............ it was the main/under car fuel pump [again].

Runs great once again.