My 99 has a bad initial throttle hesitation and then goes away. After driving for 30 miles the hesitation stops then after another 30 miles I get CEL. As soon as I clear the hesitation comes back. I get a mass air flow meter fault but I tested it and it works fine. I also test for vacuum leaks, intake leaks and it's fine. My tech didn't have a chance to really dive into it but he is stumped and the problem. The engine runs great other than that initial hesitation.Its a non-turbo.

 

Replace fuel pressure relay. Check fuel pressure.

 

Thanks MSG, I checked the fuel pressure and it reads 45 psi and it doesnt matter if I rev it or not and stays at 45. I pulled the relay and then tapped it and put it back in and its the same. Is the pressure ok?

 

could be the ETM acting up. Did you clean the intake parts (ie MAF, ETM etc)? Has your MAF been replaced with an after market brand?

 

No, still original MAF and ETM. I blew air through the MAF to clean any dirt but it was clean. I got a used one online which was guaranteed to try. I should get it this week.

 

any stuttering? check your fuel pump relay.

 

Get a new tech?

 

Now I am losing my mind, as i said before I replaced the pvc system and after that began this problem. I finally got pissed and took off the intake again to see if something is wrong and everything is perfectly installed. I thought that maybe I missed something but all is fine. Because I was getting a maf error I bought one and nothing. One question, the hose that comes out of that plastic long piece with the fuel rail is plugged into, where does that go? I have 3 nipple, the fuel rail, the bottom of the rubber intake and one on top. Can someone tell me which is which so that I am correct.

 

What really aggravates me is there are a ton of videos on this but not one non-turbo!!!!!

 

The V70 was built with the 2.4 T5. Check your local salvage yards or find a V70 that you can inspect.

 

I have tried looking for one locally and nothing. All striped or demolished. I keep thinking about it and the more it does not make sense. Everything that I removed, I made sure it was put back as it was,very little to mess up, and it still doesn't run correctly. There are only 3 vacuum lines which I tried all different ways and still nothing. The only thing that may cause this may be the that the injector rail has a hose at the end and it goes to the top of the rubber intake. The other is the long hose which goes under the intake and goes to the bottom of the intake boot. This is just crazy!!!

 

I found the problem!!

 

what was it?

 

There was a solenoid just on top of the radiator under a cover that was not connected. I am surprised no one knew this.

 

pic please. tx

 

Opened my hood on my 98 C70 coupe, 2.3 & found that solenoid had slipped out of its bracket, but the 2 connectors held it in place. Under the rad shroud on the left standing in front of engine. Going to put a spot of hot glue there to ensure it stays put.

 

Glad you found your problem, but.............

hot glue melts when it gets hot (the clue is in the name) and it isn't particularly adhesive with nonporous/nonporous applications. if your solenoid gets as hot as mine then it when be loose again in 40 miles.

I'd use JB Weld or a similar epoxy. i might also consider buying a new solenoid first because, as sure as I own two Volvos, immediately after you make it unremovable, it'll die on you.