I sure thought the fuel pump relay would be it

[ThommyKent]

The date code on your wires is the 46th month of 1995, so they are original to the car. Looking at the picture of your throttle cable it looks like cable sheath end is broken or not seated down in it`s hole. The only thing that would make your car rev up to 5000 rpm`s on it`s own would be a problem with the cable or other mechanical parts like the roller the cable is attached to.

46th month of 1995? Did 1995 have four years of months in it? (snark not directed at you) I agree that they definitely look to be the original equipment, and I did replace them.

I'll try to dig up a throttle cable. On a scale of 1-10, how much is it going to suck to replace that?

Whoops 46 week of 1995

[belyle]

I agree that my throttle cable needs to be replaced. I'll test it tonight by disconnecting it and making sure the throttle moves freely. Do you have a good online source? My local Volvo dealer wants eighty bones for the cable. I've found several sources ~$50 online (shipped), but the websites are a little uhh sketch seeming.

[cn90]

If you have auto trans, then the throttle cable is PN 9157601....$40

I buy from Superior Volvo in Kansas City, good service, freight is low. Give it a try:

http://www.thevpstore.com

PS: Don't forget to re-attach the kick-down connector.

[belyle]

Well, I feel like a dunce. I checked my throttle cable when I got home only to find that the housing was snagged on the barrel adjuster, pulling the cable tight. I freed the housing and it's idling normal again. I still have to take it out for a test drive to make sure it behaves at temperature though.

Hey all, first off thanks for your patience while I asked questions that you've all probably seen and answered 100 times before. It would have been hard going for me to fix my car without your guys' help. The Haynes manual is next to worthless for troubleshooting like this.

I took the car out for a spin tonight and all I have to say is "HOLEEEY SHEEEEUUUCKS!" If someone had told me I'd have this much more power just from replacing the ignition system, I would have done it a year ago when I bought the car. I gave it a little gas off a stoplight and was doing 70 before I knew it. In a 40 zone... I got lucky there wasn't a cop near there like there normally is.

I'm still going to pick up a throttle cable next payday, but for now it seems like everything is A-OK. No more stuttering or stumbling at idle. Even the pulsing under not-full load seems to be greatly reduced. Next up is getting all new vacuum lines and a battery...

[ThommyKent]

Excellent! Just leave the throttle cable. If it moves smoothly there is no reason to replace it and open up another can of worms.

[belyle]

I do not have a sufficient vocabulary to adequately express my current frustration.

I drove my car to work today for the first time since doing all the repairs. Just to recap, here's what I've done:
[*]Replaced fuel pump relay with brand new
[*]Checked pressure at fuel rail and it was 38PSI at idle +/-
[*]Connected a loose vacuum line and listened for leaks elsewhere
[*]Replaced spark plugs
[*]Replaced plug wires
[*]Replaced distributor cap and rotor
[*]Cleaned IAC
[*]Cleaned battery terminals

I knew once I got on the freeway that something was not quite right, but I went for it anyway. Going up the on-ramp, the power cut out for a second but then I was going gang-busters again. I thought that getting everything heated up and all the crud burned out would help. It was stuttering a little at low load (again). It had plenty of power once I got above about 1500 rpm, but everything below that was a little off. I do about 20 miles on the freeway to work.

I thought maybe some fresh good gas might help. Stopped at the Chevron and filled it up. The pump didn't shut off and ended up spilling about a gallon of gas all over the side of my car and the ground. I'm pretty sure that's irrelevant to the story, though. Car started right up after filling.

I drove the last couple miles to work. The entrance to my work is at the bottom of a fairly steep hill. I usually pull a U-turn and park on the street. In the middle of my U-turn, my steering got really heavy and I realized my car had died. No warning, no sputtering, just dead. Just like last week.

I got it barely started again, but every time I tried to shift into gear it would die. I managed to get into a parking spot (got really really really lucky that there even was one) by keeping one foot on the brake while hitting the gas to keep the RPM high while getting it into gear. That can't be good for the transmission, but I couldn't leave my car askew in the parking lot entrance.

At this point, I have zero confidence that I'd make it back home. There are a couple decent Volvo mechanics in Redmond and I have at least a little confidence that I could drive the ~5 miles to either of them without getting stranded. I can't really work on my car in my work parking lot, so I either need to get it home or to a mechanic. A tow 25 miles to home is not a great option either, though.

[cn90]

The fact that you have 38 psi out of the fuel rail does not mean the fuel pump is OK.
It may run fine for 10 min, but hiccups for the next 30 sec, then the cycle repeats until it fails altogether.
At that mileage (210K), the fuel pump is on its last legs.

Easy to diagnose:

Read this DIY: 1998 Volvo V70 Fuel System Troubleshooting Tips:
https://www.matthewsvolvosite.com/forums ... hp?t=52252

Set your DMM to Ohmmeter.

Read Step #5: Fuel Pump winding has a resistance of about 1.0-1.5 Ohms. Mine was 1.0 Ohms (measured via 31 and 87 on the socket).

If your fuel pump resistance is out of this range, then time for new fuel pump.

Search forum for "Walbro" vs "Bosch".

[erikv11]

I sorta doubt it's the fuel pump, they usually either work or don't. Or if they crap out, they do it quickly. But won't hurt to check.

I didn't read the whole thread - have you checked the MAF yet?

[jblackburn]

Lets not throw expensive parts at the car that aren't necessarily bad. Fuel pumps tend to either work or they don't, about 90% of the time. I've only had 1/3 die on my high-mileage cars. Sometimes they're weak, but it tends to show itself more at higher RPM.

OP, my next recommended step would be unplug your battery, tap the brakes to drain the charge, and then unplug the mass airflow sensor and take the car for a quick spin around the block and see if it stutters on acceleration. You've got codes showing a slow response, etc. This will put the car into a "default" mode for fuel trims, etc. If it can idle/drive well without stumbling, you may have found the problem with low RPM response.

[belyle]

I sorta doubt it's the fuel pump, they usually either work or don't. Or if they crap out, they do it quickly. But won't hurt to check.

I didn't read the whole thread - have you checked the MAF yet?

I have not yet. I can try that. One of my buddies at work is going to let me use his driveway and garage so I only have to limp it a few miles rather than trying to get it home tonight. I'm having my wife bring up my code reader so I can check to see if it threw anything else.

Lets not throw expensive parts at the car that aren't necessarily bad. Fuel pumps tend to either work or they don't, about 90% of the time. I've only had 1/3 die on my high-mileage cars. Sometimes they're weak, but it tends to show itself more at higher RPM.

OP, my next recommended step would be unplug your battery, tap the brakes to drain the charge, and then unplug the mass airflow sensor and take the car for a quick spin around the block and see if it stutters on acceleration. You've got codes showing a slow response, etc. This will put the car into a "default" mode for fuel trims, etc. If it can idle/drive well without stumbling, you may have found the problem with low RPM response.

I have to be able to drive it long enough for it to warm up before I notice the stuttering. The other night that I thought I had it fixed I must not have been driving it enough to get hot. I guess it was below freezing out. I can certainly try it though. Driving with an unplugged MAF will throw codes and kill my mileage, but it won't hurt anything for short term, right?