25 replies to this topic

[SANTINO]

Hi,

My NA '96 Volvo 850 has not been starting during cold and/or damp weather. The vehicle will crank but will not fire up. I've done some research and many have suggested the possiblity of a bad Fuel Pump Relay. I removed the relay (#103) and jumped it with no success. I can hear the fuel pump working with the relay installed but not when it is removed with the jumper installed. What does this suggest? I've also read that it could be the Fuel Injector Relay. How can I test this relay?

Also once the vehicle sits for a while and the outside temp warms up, I have no problem starting the vehicle.

Please help!

P.S The car has about 200K on it. Ignition Wires, Spark Plugs and Distributor Cap and Rotor were replaced at 130k

[FCP Groton]

Most of the time when it is a cold start issue, it is the intank fuel pump.

[SANTINO]

FCP Groton, on 04 November 2009 - 08:16 PM, said:

Most of the time when it is a cold start issue, it is the intank fuel pump.

The thing that has me stumped is that I can hear the fuel pump being primed when I have the key in the II position.

[DonutsDemise]

SANTINO, on 04 November 2009 - 08:31 PM, said:

The thing that has me stumped is that I can hear the fuel pump being primed when I have the key in the II position.

what are your fuel pressure numbers?

[SANTINO]

DonutsDemise, on 04 November 2009 - 08:43 PM, said:

what are your fuel pressure numbers?

I haven't checked that yet. What should it be?

[mbsl98]

I'd think that your problem is more likely something like the ETC (Electronic temperature control) under the thermostat, particularly if you can hear the fuel pump prime when you turn on the key. A very quick fuel supply test is to turn on the key to Position II but don't try to start. Then open the hood and press something into the tip of the fuel line schrader valve (valve that sits at the end of the fuel rail along the top of engine above the intake manifold. There should be fuel released under pressure when you press in the valve stem, and the pressrue was created when teh pump primed. If there is fuel there, I'd think the pump was working at least enough to start. The ETC acts like a cold start enrichment system, and sends signals to enrich the fuel mix if temperature is low, just like an old fashioned choke. If it is cold and fuel not rich enough, no start just cranking.

[Ian Carr]

what oil are you running? My friend used to run 15w-40 in his eclipse turbo and said that when it was cold it would not start and had to wait for it to warm up a bit.

[SANTINO]

mbsl98, on 05 November 2009 - 03:46 PM, said:

I'd think that your problem is more likely something like the ETC (Electronic temperature control) under the thermostat, particularly if you can hear the fuel pump prime when you turn on the key. A very quick fuel supply test is to turn on the key to Position II but don't try to start. Then open the hood and press something into the tip of the fuel line schrader valve (valve that sits at the end of the fuel rail along the top of engine above the intake manifold. There should be fuel released under pressure when you press in the valve stem, and the pressrue was created when teh pump primed. If there is fuel there, I'd think the pump was working at least enough to start. The ETC acts like a cold start enrichment system, and sends signals to enrich the fuel mix if temperature is low, just like an old fashioned choke. If it is cold and fuel not rich enough, no start just cranking.

I checked the schrader valve and there is fuel being released under pressure. How can I test the ETC?

[SANTINO]

SANTINO, on 06 November 2009 - 01:34 PM, said:

I checked the schrader valve and there is fuel being released under pressure. How can I test the ETC?

Any tips on testing the ETC and the Fuel Injector Relay?

[SANTINO]

Hi,

The no starting problem has started again and its definetly related to cold damp days. When I had it sitting in the garage it started no problem. After having left it outside in the cold for several days the car didn't start.

When checking fuel pressure at the shrader valve with the key in position II should there be constant fuel pressure? When I depressed the valve a minimal amount of gas is released under low pressure and then it stops. Is this normal?

[Milo]

I also have this problem. I live in LA so I haven't really bothered to fix it due to the fact that it's almost never cold enough to be a problem. However the last time I asked almost everyone was sure it was the ECT.

My Thread

I cleaned the IAC and it didn't help BTW. I'll be swapping the ECT in the next few days, likely tomorrow evening if I can get a 7" T40 bit at HD tomorrow after work.

[pcguru000]

This is hilarious- i am having this exact same issue- i think i posted it in the wrong forum (99 and later - mods delete that or move it if you want)

Ive had multiple battery drain issues (lights stuck on, amp wires crossed... dumb stuff) but this time I had a good 12.5 volts on the batter, really nice battery with loads of power, cranks the car 20+ times but no start..

I hear the fuel pump, but still no start... tried hitting the accel. pedal a bit but no difference.

I thought maybe the IAC is stuck because when i stopped and pulled the key out and opened the hood- (car completely off) I get this buzz coming from under the throttle body cover... (is that normal?)

I do hope there is a easy or obvious solution here- really **** tired of my car not starting... freakin put over 8 grand into it by now easily and its disappointing...

makes me want a honda lol- sometimes i think that the only reason volvos are such good cars and they run SOOOO long is because the person that has the money to buy a volvo ... has the money to fix a volvo.

*sigh*

Ill keep an eye out on this topic i suppose- really do need a fix for this though...

[Milo]

Quote

I thought maybe the IAC is stuck because when i stopped and pulled the key out and opened the hood- (car completely off) I get this buzz coming from under the throttle body cover... (is that normal?)

Pretty sure that's normal. Mine does it too when it won't start. In my previous thread someone said it was normal, I pulled the IAC and cleaned it, spins fine so I think it's OK.

Seriously I think there is overwelming opinion that this is the ECT. It's a pretty cheap and easy fix too, you just need to make sure you have the ECT, it's washer, and a 7" T40 Torx bit like in the Bay13 instructions. You should also be able to do the job without draining coolant by clamping off the large hose before removing it. You might have to top off the coolant but should be no more. I'll post a followup if I get lucky, do the job tomorrow night, have an unusually cold morning on Tuesday and the car starts with no problems.

[pcguru000]

Interesting - i will look at bay 13 ... i dont even know where the ect is right now...

Thanks for the help- ill keep checking back here

[pcguru000]

SANTINO, on 06 November 2009 - 01:34 PM, said:

I checked the schrader valve and there is fuel being released under pressure. How can I test the ETC?

I think *think* that we can't actually tell- obviously if the fuel pump is working then you would get a spray of gas off the end of the fuel rail...

If the ect is working properly on a cold day then i would assume that spray would be MORE... however im not sure we would notice without having a fuel rail pressure checker... i think you can get one at pepboys for 15 bucks...

hate these things i cant quite diagnose...

if there is an obvious way to test the etc id love to know - what exactly goes wrong with it? is it a circuitry issue or something mechanical? Also- for those out there that will need a new one :

Autozone

[Milo]

pcguru000, on 07 December 2009 - 02:34 AM, said:

I think *think* that we can't actually tell- obviously if the fuel pump is working then you would get a spray of gas off the end of the fuel rail...

If the ect is working properly on a cold day then i would assume that spray would be MORE... however im not sure we would notice without having a fuel rail pressure checker... i think you can get one at pepboys for 15 bucks...

I don't think you would see a difference, the fuel pump and regulator system should never pump different pressures. The ECT returns cold to the computer and the computer leaves the injectors open longer (AFAIK, I might be wrong here).

Quote

hate these things i cant quite diagnose...

if there is an obvious way to test the etc id love to know - what exactly goes wrong with it? is it a circuitry issue or something mechanical? Also- for those out there that will need a new one :

Well the obvious way to test it would be to put a multimeter on it and test it's resistance, then compare it to a table that shows what it's resistance vs temperature should be. If I don't do the job tonight for whatever reason I'll use my new ECT and test it to build a table (I couldn't find one online anywhere). If your ECT is giving false resistance readings then the engine won't be giving the car enough fuel to cold start.

ECTs are thermistors they are solid state resistive sensors that change in resistive properties as the temperature changes.

The big however:
I've thought of this before, so I took my new ECT and connected it to the electrical system but did not replace the old ECT, this way it the new one should have been feeding resistance to the computer but it was just sucking air instead of coolant (I know it doesn't actually suck). This did not work however. One possibility is that the good ECT which was in my glove box wasn't cold enough to tell the computer to feed enough fuel to make it start (the same problem that you'd have with a broken ECT).

Another trick might be to find out what the resistance of the ECT is when it's really ALL GLORY TO THE HYPNOTOAD cold (like in the freezer cold), then grab a power resistor of that value and stick it across the ECT's harness leads. Should tell the computer to run very rich, so no matter if it's warmer than "ALL GLORY TO THE HYPNOTOAD cold" the car should start, albeit running very rich. Leave it like that until the car warms up a bit then swap back to the broken ECT.

[Ipd]

Same issue this AM with my car.

Old pump pulling too much current, burned contact on fuel pump relay.
New pump and relay, runs like champ.

I pulled the relay cover off and cleaned the contacts then started the car to confirm.
Measured amp draw through the pump and it was way too high.

BTW it's relay marked 103 under the fuse box cover in the engine bay...

[SANTINO]

This weekend I changed my plugs, distributor cap, rotor and the fuel injector relay. I had ordered a fuel pump relay (103) but it wasn't working so I have a replacement coming. The car runs so much better....until tonight. I now have the dreaded flashing up arrow and the flashing mode selector and the car just won't start. It cranks...that's it. My reverse lights have been intermitent ever since I bought the car but I never did anything about it. I going to assume that my PNP switch is gone. What's next????

[SANTINO]

Just pulled the codes and got a P0120 - Throttle Pedal position Sensor/Switch ”A” Circuit Malfunction. Could this cause the flashing arrow and no start condition?

[JordanW]

SANTINO, on 08 December 2009 - 03:25 AM, said:

Just pulled the codes and got a P0120 - Throttle Pedal position Sensor/Switch "A" Circuit Malfunction. Could this cause the flashing arrow and no start condition?

the GREY fi relay on the fan shroud... or the TPS itself. Check the wiring to that grey relay on the fan shroud!