3126E Surge

[Eric Lis]

Have a 2002 Newmar DSDP 3126E/330HP Had it at the Cat dealer here in Riverview. Routine maint filters etc. After the service developed a surge at idle in gear at a stop. Returned to Cat. They replaced 2 things. IAPCV valve which didn`t help. They then replaced the Injection Actuation Pressure Sensor. Motor acted right for a short period of time. Engine idles fine in Neutral. The original surge was about 125 rpm now it`s down to 75 RPM. Has anybody experienced this? Now they want to get all the gauges hooked up under the valve cover etc to do further diagnosis. I can live with the surge just don`t want to hurt any components by running it this way. Any help out there folks.

Eric

[Ret Syntst]

I also had a surge in engine RPM (3126E 330 hp Cat) and they replaced an oil pressure sensor - fixed it right up.

[Eric Lis]

Injection Actuation Oil Pressure sender fixed it

Thx

[Eric Lis]

Well the Surge has returned! Took it back to RingPower for more analysis. Hopefully the extended warranty takes care of it this time as they mention it may be extensive. Short of a possible HEUI replacement they are headed first towards injectors o rings, and possible electrical connectors under the valve covers. I have left it with them for the time I`m away working. Should hopefully get it back fixed this time around the 16th. Fingers crossed as we leave for the west coast and Sturgis on the 15th of July.

[Eric Lis]

UPDATE! Spoke with RingPower yesterday, and they say Coach is fixed. I will pick it up Monday morning for a drive.
They replaced a few parts which make complete sense after doing some research on the oil system and the HEUI pump schematics. After hooking up related pressure gauges they found a flux in the oil pressure at the filter housing while the engine was at idle. After replacing the associated seals,springs, and plunger they say all is good. My question to them continues to be "I never had this problem till you changed the oil"? I will have to see what kind of oil pressure the gauge reads now. It was a steady 40 psi before at 1600rpm. Never saw the flux at idle from the elec gauge. I`m guessing from looking at the schematic of the oil pressure system the oil was possibly bypassing a small amount, and being there is not as much flow at idle the HEUI pump was asking for pressure and the oil system couldn`t deliver. I will update after driving it on Monday.

[Eric Lis]

Update. Drove around quite a bit yesterday, and also a new set of front tires getting ready for trip west. All is good, and carrying a bit more oil pressure at cruise. the short of it. There is a ck valve located in the oil filter housing they replaced.