Volvo 5.0 gxi Stalls at idle. Hard start.

[QBhoy]

I have no scanner to get any data.
It had no iac songe before. I purchased one and put it in. The only change I noticed with the sponge is the iac flow is nice and quite no more loud suction at iac. I haven’t changed plugs yet was going to today. Plugs have about 8hrs on them since the new long block.
No sing of air suction at fuel anywhere. Old fuel pump was loud. Brand new fuel pump is about 1 hour run time and sounds great.
I tried spraying everything with carb cleaner last season and found no vacuum problem.
If engine is cold I fire it up. Runs for a second then stalls.
If engine is cold I can unplug tps sensor. Fire it up and idle perfect.
If engine is warm I can fire it up and idle perfect.
I’m tempted to buy a rinda scan tool but I fear I won’t know what to read on it. Like what to cross reference info to. I have a solec service manual.
I really don’t want to have to open throttle ,warm up engine, then back down to idle every Time I touch the boat with a cold engine. This efi makes me miss my old carb boat. Thanks.

Ok. And you’re certain that the diz cap is perfect ?
Is the throttle body clean and no crap or gum having an effect on the mechanism?
I’d take the plugs out for a look. Make sure there is no sign of water in about there.

 

[mallardmasher]

So I finally have a cold engine idle. Yay.
Changed many sensors. Changed plugs from .45 gap they put in with new long block to the recommended .60 and engine finally cold idles. The only problem I have now is when engine is under 110 degrees and I go to move throttle just a tiny bit. It will want to hesitate and stall. If I move throttle faster and skip over that initial opening of throttle there is no problem. If engine is warmed up then that tiny bit of throttle is no problem.
It feels like I might not have the throttle stop p screw in the exact spot it should be in. I tried setting it to the pic in above posts with the .020 gap on throttle plate but it seems way to high and idles way too high. Even setting it to the .020 puts the throttle screw way down in there and past the original paint marks on the throttle linkage. Does anyone know what the throttle stop plate screw/throttle plate gap should be on a Volvo penta 5.0 gxi-d. I tried this pic recommendation but it causes too much idle.

 

[alldodge]

The IAC should read around 40 during idle, it's currently reading 75 so it doesn't have enough area to control idle within parameters. Giving it fast throttle jumps past the IAC area so it doesn't stumble or die. Increasing the throttle plates gets to much air in so idle is to fast

To adjust plates it would take gauge wires instead of feeler gauges

Might look closer at the IAC and possible vacuum leaks

 

[BlueEyedDolphin]

Volvo 5.0 gxi. Fuel injection. I need some of your expert advise please.
Runs excellent through all rpm except idle. Needs a tiny bit of throttle in neutral to start engine. If I let it run for a min with throttle open and back it down to idle the engine will almost stall but catch itself and idle and a can run great all day until I turn engine off.
If no throttle is given it sarts for a second and stalls when warm or cold. I thought it was the iac so I put in new iac but didn’t resolve problem. The throttle body sounds extremely loud sucking air in at the top. When I remove spark arrester I can really hear the loud sucking of air draw in around the plenum. Is my iac out of wack ? Like the circuit is forcing iac to stay plunged closed, forcing the air to be draw in at plenum ? I’ve never remembered this loud vacuum sucking. It’s loud so I’d imagine I would have noticed this before. Any input is gratefully appreciated. Thanks

Did you get an answer to that? I just just changed my IAC and it fixed the problem. It was stuck closing the air passage. From a 5.7L OSiE

 

[mallardmasher]

The IAC should read around 40 during idle, it's currently reading 75 so it doesn't have enough area to control idle within parameters. Giving it fast throttle jumps past the IAC area so it doesn't stumble or die. Increasing the throttle plates gets to much air in so idle is to fast

To adjust plates it would take gauge wires instead of feeler gauges

Might look closer at the IAC and possible vacuum leaks

I used a flat plate gauge. I will try a wire gauge. I’ve tried three iac valves now. The cheepo replacement had a different shape pintel. The gm replacement had the same pintle. The oem one had the same pintle. Both the gm replacement and oem replacement work the same and move the same. I found it fires up and idles best with the foam iac filter removed. I’ll try a wire gauge and do the plate gap , I take it the flat gap gauge was not giving me a tru gap because of the throttle body rounded shape ?
Thanks

 

[alldodge]

Yes

 

[mallardmasher]

Yes

I’m looking online and auto stores and can’t find a wire gauge down to .020

 

[alldodge]

Agree, hard to find, and for the most part getting it exactly may not be that critical
Had a MPI Throttle body that was damaged and had to readjust using hand tools. Adjusted and all worked as needed. So the question is did I get lucky or did I do it correctly, don't know

Could reduce opening a hair, and see what that changes. Just need some real good readings to see what is changing as adjustments are made

 

[mallardmasher]

Agree, hard to find, and for the most part getting it exactly may not be that critical
Had a MPI Throttle body that was damaged and had to readjust using hand tools. Adjusted and all worked as needed. So the question is did I get lucky or did I do it correctly, don't know

Could reduce opening a hair, and see what that changes. Just need some real good readings to see what is changing as adjustments are made

I found one from summit racing. Should be here in two days. I tried to compare the feeler gauge to small cotter pins and found a one just a hair over .020. It looks like it will still set that stop screw farther than it was from factory. I was the one who scraped the paint off to access the stop screw since I could hear engine starving for air. I can almost get screw to sit exactly where the old paint dimple is on the throttle linkage. If I go a hair deeper I idle at about 900 and that tiny second of stall at barely opening throttle is gone. . If I go a hair shorter I idle at 550-600. The sweet spot I’m sitting at now idles 650 and sounds great.
I guess I really won’t know anything until I put it in the water and get some back pressure. Let it idle in gear and then play with stop screw. Once it’s warmed up that tiny second of wanting to stall at barely opening throttle is gone. Thanks for all your help if it wasn’t for your guys advise and help I wouldn’t have found cold idle.

 

[mallardmasher]

Agree, hard to find, and for the most part getting it exactly may not be that critical
Had a MPI Throttle body that was damaged and had to readjust using hand tools. Adjusted and all worked as needed. So the question is did I get lucky or did I do it correctly, don't know

Could reduce opening a hair, and see what that changes. Just need some real good readings to see what is changing as adjustments are made

So I set it exactly.” .020 on each side of throttle plate. It idles high. A steady 1000rpm. No surging no fluctuations. Just a steady high idle. I know I should be down around 600-650 at idle. How much do you think idle will drop once in the water, in gear, with some back pressure ? Will the iac valve work its way into lowing the idle after some running and re learning . I let it idle on muffs for awhile and it just sat at 1000rpm. Never dropped down. If I adjust that screw and close the throttle alot much shorter than the .020 gap it will idle at 650 but takes two turns of the key to start it to stay running. Runs for a second and stalls. Restart and idles fine. I watch the iac and it’s doing its job of closing during throttle and opening when idle. I’m afraid to set the .020 gap and drop it in the water to find out I’m going to fast into docking or channels. I’m wondering if the back pressure of water will bring me down a couple hundred rpm if I’m at 1000 on muffs. If I’m on muffs at 650 rpm how much rpm will drop in water,in gear idle Thanks.

 

[alldodge]

There "should" be no drop in rpm in or out of gear with the MPI, that's what's the IAC for. What is the reading of the IAC when it's idling at 1000? If its below 40 then it's trying to slow but that's all it has.

Need to compare IAC readings with idle rpm

 

[dubs283]

Need to compare IAC readings with idle rpm

OP needs diacom to graph/record data items for comparison and perform any available tests on specific components

 

[ripjmk]

You don't have the base timing jumper still in the diagnostic connector do you?

 

[mallardmasher]

No the jumpers not in. No one around me has the diacom software for Volvo. They all have merc stuff and merc mechanics. I was tempted to buy the rinda scanner tech mate but since I’m no mechanic I won’t know what any of the data means. Looking online this 2003 engine doesn’t seem to be electronicaly adjustable with scanner like the newer engines.
When I set the throttle plate to the .020 it is definitely deeper then the original paint dimples from before i scrapped the paint off to open plate more. Can see the old paint dimple on throttle from where screw sat before they painted engine red at factory. I can watch the iac do its job and move in small increments. When I try to plug iac hole with finger I can see it backing out more to compensate my finger blockage. Both the gm Delphi iac and the oem iac appear to react the same.
I’m thinking I’ll just move it back away from the .020 gap and live with having to turn key twice to start it. Also wondering if the cheeper map sensor I purchased is not up to par compared to the expensive oem one. Map sensor I bought was $50? Oem Volvo one is $300 ? When I changed map sensor everything smoothed out at idle better but also did recommend plugs at same time.
Thanks

 

[alldodge]

The MAP sensor is a GM 1 Bar (1 atmosphere) and is not worth 300
While they are simple sensors, aftermarket is a crap shoot

 

[dubs283]

Map sensor from GM (delco) is what you need.

Techmate won't help you much. Full diacom software on a laptop will allow for recording, graphing comparisons and component testing

Hopefully it's the map sensor, try a quality one and test.

 

[mallardmasher]

Volvo wants $300 for oem map. I found a new oem map sensor from a marina next state over for $100. I purchased it and put it in. Was still in original packaging.
Way worse ,wouldnt even stay running. Tried letting computer and iac relearn and it was still worse. I figured a few starts and some throttle it would settle in. So I Removed it and put the $50 one back in. I’ll just have to live with Turning the key a few times to cold start idle. Or open the throttle a hair to cold start idle on first turn of key. Thank you guys for all your help. You guys outshined my local mechanic. Thanks.