Convertiblau! My 1996 BMW 328iC

[Jake]

I got an email from the PO, detailing what he did to try and chase down the P1188 code. Sounds like I have a few things to look at but any thoughts would be appreciated.

1. bench tested MAF and its operating within spec (swapped another MAF from different E36 no difference)
2. removed and checked intake/MAF to throttle body boot for dry rot/cracks, none detected
3. Replaced oil separator (pcv) and grommet as well as all oil separator hoses to intake boot, front intake.
4. Smoke tested the whole vacuum system and can see no leaks
5. cleaned throttle body completely, checked all TB gaskets and they look good.
6. checked gas cap for broken seal, etc, . it fits well and seems to seal well
7. Replaced both pre-cat sensors (one of them bench tested bad the other good)
8. bench tested secondary air system valve at exhaust, tested ok, replaced gasket
9. replaced small vacuum line from secondary air system valve to intake tube
10. removed, checked and cleaned IAC valve, checked grommet to intake for cracks etc. no problem found; replaced IAC supply hose
11. removed and checked vacuum canister and replaced all vacuum lines to and from canister
12. replaced fuel filter
13. visually I cannot see any cracks in the exhaust around the pre cat o2 sensor area
14. replaced valve cover gasket and seals
15. visually inspected intake tube from air cleaner box to TB, no cracks, holes, etc.
16. checked secondary air system, including exhaust valve and small vacuum hose, all good.
17. swapped the 1/2/3 coils with 4/5/6 coils to see if p1188 code (bank 1) moved to P1189 code (bank 2), erased code and it threw 1188 code within 10 miles
18. did same thing with fuel injectors as 17 above same result; cleaned all fuel injectors while i had them off
19. one hose i did not replace that could be the culprit is the dip stick tube to pcv hose (its cheap)

Otherwise, he did all of this to it:

- 2 new rear shocks
- 2 new rear lower control arm bushings
- new bosch water pump, thermostat (92 c), thermostat housing
- new aluminum radiator, upper/lower hoses
- new drive belts