we just had a new radiator installed in our '94 855T and now the car starts a little rough - more cranks before it fires - and the idle is noticeably choppy, sometimes acting like it wants to die. any ideas on how to trouble shoot this or what approaches to take?

thanks
matt b

listen for a vacuum leak. There is a vacuum line that runs across the front toward the battery that is easily separated. the joint is just to the right of the rad on the battery side.

as posted last night, I think I got it by correcting the vacuum routing through the EGR controller, it was backwards. new part image at fcpgroton.com helped clear up the routing (yellow top to egr, white bottom to intake vac tree).

thanks

Does the idle air control valve buzz when the ignition key is turned on?

yes it does.

You might want to check for water around the distributor and under the spark plug cover ... if they took the radiator out the top way, perhaps they slopped some coolant around. Or maybe even if they did take out the bottom, they may still have slopped it around when refilling.

--
'96 850 and '83 244 DL both at about 190K; the '81 GLT 245 @ 280K is available

Did you replace the radiator after/because the car overheated?
If so, I would check for a warped head. Depending on how bad it is, if you take off the coolant reservoir cap and turn the engine over--if it splashes you probably have a warped head.

No overheating, just a leak at the upper coolant hose connection that was not affected by new hose and clamp. There was a crack in the plastic nipple and I didn't think a good repair was possible. I just checked and there are no codes in the DTC system, at least not in any of the A modules.

I will do your test and see what the results are. Wouldn't rule out a warped head, though there was no overheating. I've been using the car as a sort of mule, hauling lumber, gravel, sand, etc, for various projects, and no doubt putting various components to the test.

thanks for the reply,

mb

Interesting, I have an 850, I put a new radiator in this July and a new leak developed. I thought it was my upper hose and I replaced it, but it was actually the overflow tank lid. The water migrated along the little hose coming out of there and ended up on the top hose so I thought it had a leak. Can you actually see the leak? Check to ensure that you plugged all the relays back in on the fan. Run the AC and make sure the fan comes on. I think I do have a head going, but I have been able to stop the leak with by adding a little more radiator fluid to thinken the mix along with water wetter to cool the temps. Alternatively, I may have gotten water trapped in the block when I flushed the system and the mix was too lean on coolant thus the pressure. Either way, its running for now.

Good luck

You still using that same mechanic?

Check your codes first. The mechanic might have left some relays undone that sit above the radiator. Or forgot to plug in a couple of vacuum hoses in the same area.

Klaus
--
Proud owner of a 1967 220S. If I had more room, I would have more Volvos.

pulled vac line from egr = smooth idle. checked lines at controller = backward. switched = all good, KOW. will post back if funk returns.

matt b

p.s. that makes two shops in nashvegas that do it almost right.

all connections look good - definitely a harder start when warm, and a high rev start when cold. any ideas? fuel pressure reg?

matt b

check the connection on the temp sensor... located just below the upper radiator hose on engine block... It may have come loose or broken.

bob
850 940 p1800

yeah, gave him a break and did a bunch of my own work and now it looks like I should have kept it that way. relays and vac lines look good, but maybe I should disconnect and reconnect and see what it does.

thanks.

matt b