The car doesn't want to start quickly. I'm a mobile mechanic and I'm fixing this car for a customer.

Has Rex Regina pump intank only. Replaced filter and replaced FPR but I need to swap the regulator for a Rex Regina regulator. Also went ahead and threw in four injectors.

I have yet to mess with the relay yet, I will be doing so very soon. I did remove the access panel and hook my gauge up to the pump itself. She topped at 39 psi or so. Wouldn't go any higher. At the rail however, max is 34psi idling, and drops to 30 under revs. Overnight she'll drop down to 20 and any longer down to zero.

I haven't messed with the cold start valve, I do have one to swap in but haven't. The pump primes everytime you cycle the key on but I can't get it to start in decent time. Something's causing a loss in fuel pressure.

Volvo can't get me the actual spec on the Rex Regina pump, I just know a new one is in the $300s-$400s.

 

Have you pulled codes? Hard start cold or hot...or both? How's the voltage on the O2 sensor?

 

No codes stored for ignition or fuel system.

Once you force car to start with starter fluid or just plenty of cranking she'll run fine and drive fine and you can cut her off and crank her right back up. Just after a time sitting she doesn't want to start, just turn over and turn over.

I unplugged the fuel pressure regulator one day and she still didn't want to start. I want to think it's fuel pressure then again I don't and then again it does drop pressure while sitting.

NOTE- I will say this cause even I forgot about it. The car has 235K on it. Meaning the pump probably has 235K on it. Pressure at the rail is supposed to be 43psi while I can't even get the pump to push anything higher than 40. I'll pull the pump to inspect the sock, but I'm starting to think a fresh pump, with some fresh gas and a relay will wake this car up.

 

not sure if the regina has the radio suppression relay but if it does I have experienced all kinds of issues that ended up related to that relay. If its there replace it, $35 from autozone but having it instock is iffy. If there is a pick your own part around get a couple and it will only cost 5-10 for all of them. BTW I have gotten new ones that were bad. I want to say the Regina has one and its on the driver side under the hood around the strut mount. Little black box with a mounting clip and a plug in the bottom. Have you cleaned out the flame trap? Bad crank case breathing can do the same and the heat and pressure is pushing just enough through to make it work. Do any oil seals leak??? Thats a good sign its clogged.

 

The starting issues you've described in your last post are exactly the same as over fueling at start up. Two things...Volvo issued a TSB stating the cold start injector should be rewired to be triggered by the starter motor; often times it would run too long and cause hard starts. Check to see if that's been done. A failed engine coolant sensor or failed connection at the sensor will also cause this same starting issue. I really don't think it's the fuel pump. Regina's are a lower pressure system anyway, using a 2.5 bar fpr instead of the 3.0 used elsewhere. If you've replaced the existing fpr w/ a more common 3.0 bar you're making the issue even worse. When the ecs fails, the ecu thinks it's about 100 degrees below zero and makes the mixture pig rich.
Are you planning on billing the customer for the injectors or are you going to re-install the originals?

 

Aight, so now we're getting somewhere.

I'll be checking into everything mentioned ASAP. I doubt this vehicle was rewired honestly. But I'll look into that.

As for the injectors, I work on the cars of the entire family so they'll probably be freebies. I just want to get this car into the hands of the new owner ASAP, but I refuse to give them something and say yea just crank it and she'll eventually start if she don't drain the battery.

I can't find the exact TSB, is it somewhere on this site? Just want it in writing which wire I should splice into.
EDIT- Found a TSB on the CS fault code, but not the one for rewiring. Even the one I found is a big help cause AllData is useless for trouble-shooting these cars.

 

I'll see if I can find a procedural write up when I get to work in couple hours. On the n/a cars with hi res injectors, it's simply a matter of powering the CS inj from the starter circuit rather than from the ecu.

 

Just curious here but after trying to start it and it does not start have you pulled a plug to see if it is fuel fouled/wet.

 

I'm gonna pull all plugs tonight and check their condition. Gonna hook the pump back up. Grabbed the correct FPR today so gotta install that one. Will then unhook the CS Injector and ohm it to see if it's good and it hasn't been rewired. So I'll do that and see what happens. Once she's starting good I'm gonna give her a seafoam treatment.

Lots of free labor on this job but I have kept the car longer than I told them I would. They get a running car I work for free, fair trade haha.

 

Hey, I looked that TSB up on AllData today. There's a schematic showing Volvo's preferred method of wiring. I'd post it but that computer isn't connected to the internet. So, I printed it off with the intent of bringing it home to scan off and post but forgot to bring 'em home. If you have AllData, look up 90 740 Regina drivability issues. It's there and is applicable to all Regina cars as well as LH2.4 Bosch systems w/ CS injectors.

 

So I found the TSB. Before I rewire it I'm gonna leave it disconnected. Doesn't get extremely cold out here. My Supra has a CS Valve and my homeboy says he unplugged his ages ago and has never had an issue starting his car here where we are.

Anyways, pulled the plugs. All black with carbon deposits. Could be worse, but could be a lot better. I believe two were moist, two weren't. One plug had burn ring around the porcelain.

So a tuneup is in order. Installed the correct regulator today as well. Now gotta call them about the tuneup.