D4D irregular idle and fault code

[duncs84]

Hey guys new to this site, plenty of great info here and plently of helpful blokes. Anyway have an ongoing problem with my truck that is starting to give me the sh!ts.

My truck: 06 MODEL D4D, no chip, 3 inch exhaust (taipan), auto, 151000 kms

12 months ago (100000 kms) started to get the death rattles, took my truck to a denso agent and 2 injectors stuffed. So did things properly had all 4 injectors replaced, pump rebuilt and injection lines cleaned. In addition to this i fitted a fuel water separator, cleaned & pressure tested the intercooler, removed & cleaned entire egr system and intake manifold. My turbo was also pretty much stuffed so i a got a new one. All back together and she was like new again, quiet, smooth and plenty of power. But over the last 10000 kms she has been playing up big time.

Problems: Every couple of days she throws up a fault code (EGR flow low) and the engine light comes on but there is no apparent loss of power. This code is not constant and when it is cleared it might not come back for days, but other times it comes back straight away. It also does not idle well (doesn't matter if it is hot or cold), the engine sounds like it is choking for air or fuel. Both toyota and the denso agent have had a look at it and agree that something is wrong but can't find the problem. So far this is what we have played with; replaced fuel filters, blown out fuel lines and fuel cooler, scanned injectors, replaced air filter, cleaned MAF sensor, swapped out EGR sensor, cleaned out EGR and intake again, put exhaust back to standard, replaced timing belt and checked valve clearances. Still no joy and everything points to the stepper motor on the turbo??? Just don't understand why she is still idling funny??? Anyone got any ideas

[D4DEVIL]

Mate check on here for egr cleaning guide. I had my truck done a few months ago by a mechanic. It has 70,000 km on it. They pulled off the intake from head to intercooler and it was clogged up with crap. Garranteed this is what's wrong with yours. Mine wand cleaned out and head intake ports cleaned and the truck is like a different beast, idles great, power plus, sounds better. I'd you can afford it, get it done or do it yourself. Feel free to message me questions.

[Hellbound]

If the EGR flow code is thrown then you know exactly where to look, i would take it all apart again and make sure everything is tighten up properly with no air leaks between the gaskets as this will give the symptoms you describe. Also check that every single vacuum line went back exactly where there meant to go as this would also give off that code, use the pictures on the thread title - How to clean the D4D intake and EGR sytem - as a reference. Did you install a blanking plate on the egr system or anything like that either?

[duncs84]

No blanking plate, no chip and exhaust is back to standard. Went back through everything, all of the vacuum lines are hooked up correctly and everything is tight and sealing properly. Reset the engine light and everything was sweet, took her 4 spin and 100kms later still no engine light, then just as i pull back into the driveway on comes the light, hop out and sure enough she is idling funny again. Guess i will just have to start from square one again and work through the entire intake and egr system.

[cambelt]

Hello
What was the outcome or are you still working woth it .
Dave

[duncs84]

Finally managed to sort out all of the ongoing issues with my lux. Anyway after rechecking the entire EGR system (and flushing the EGR cooler) my mate and I were over it, so he called in a favour and we dumped my car at a different Toyota dealer. 4 days later and the engine light was gone, turned out to be a dodgy vacuum solenoid that was only playing up intermittently. The mechanic who worked on it was also a little concerned about the slightly irregular idle and that the engine was a little rattly, so he scanned the injectors again and checked the valve clearances again. Valve clearances were out of spec (makes me wonder if valve clearances were even checked 1st time around) so after a bit of shimming and some new buckets everything is back to normal, well except my bank balance. Just glad to have her running again but won't be too long before i palm her off and get something a little more reliable, then again maybe I just got lemon.